Starmer says that over the last year alone Iran has backed more than 20 potentially lethal attacks on UK soil, adding that "each we have foiled".

He says it's "clear the Iranian regime must never be allowed to get [its] hands on nuclear weapons".

The PM adds that the government is asking "all British citizens in the region to register their presence so we can provide the best possible support".

The government is also asking citizens to monitor Home Office travel advice which is being regularly updated.

Starmer adds that "we all remember the mistakes of Iraq and we have learned from those lessons".

"And UK actions must always have a lawful basis and a viable thought through plan," he says.

Starmer explains why he changed his mindpublished at 15:47 GMT

15:47 GMT

Nick Eardley
Political correspondent

The prime minister is explaining why he changed his mind - to allow the United States to use British bases to bomb Iran.

The government is at pains to say they are only giving permission for defensive actions - to destroy Iranian weapons "at source".

Starmer says this is legal under international rules because it amounts to "collective self defence".

But Parliament is not at one on this. The Conservatives, and plenty of other MPs, think the government should have taken part in the initial US and Israeli strikes.

But others - including some Labour MPs - are worried about any involvement at all in facilitating US strikes.

Image source, Reuters

Starmer then says that the US has requested permission to use British bases to be able to stop Iranian missiles at source, where they sit in storage depots or are readied at launchers.

The prime minister says he accepted this new request "in order to prevent Iran firing missiles across the region" and killing civilians.

He stresses, though, that the UK is not joining the US and Israel's offensive strikes.

The prime minister says France and Germany are also prepared to allow US activity on their bases in order to destroy Iran's missile-firing capability.

Starmer says Iran's approach is becoming "even more reckless".

The PM says it's his duty to protect British lives, which he says is why they put British jets in the air "as part of co-ordinated defensive operations".

Those operations have already been effective, he tells the house, including taking out a drone heading towards a base housing UK service personnel.

Image source, Reuters

Starmer says Iran has lashed out across region and has launched "hundreds of missiles and thousands of drones at countries that did not attack them".

He says there are an estimated 300,000 British citizens in the region, including residents, family on holiday and those in transit.

He says Iran has hit airports and hotels where British citizens are staying. "It is deeply concerning for the whole house and whole country", says Starmer.

Starmer adds that last night a drone hit RAF Akrotiri in Cyprus. He says that it is important for him to say that our bases in Cyprus are not being used by US bombers.

The PM adds that the strike on RAF was not in response to any decision that we have taken.

Nick Eardley
Political correspondent

I’m in the Commons chamber for the prime minister’s statement on the situation in Iran.

There are a huge number of MPs seeking to speak - such is the interest events of the past 72 hours.

The prime minister accepts that US President Donald Trump has "expressed his disagreement" with the UK's decision not to get involved initially.

"But it is my duty to judge what is in Britain's national interests," Starmer continues, saying he stands by his choices.

In an interview with the Telegraph, Donald Trump said the UK prime minister "took far too long" to accept a US request to use British military bases for "defensive" strikes on Iranian missile sites.

Image source, Reuters

Prime Minister Starmer is on his feet.

He starts by saying the UK was not involved in the initial strikes on Iran and calls that decision "deliberate".

The PM says the best way forward is a "negotiated settlement" where Iran agrees to give up "any aspiration" to develop a nuclear weapon, and ends "its destabilising activity" across the region.

We're about to hear from Keir Starmer, who's going to be fielding questions on the situation in the Middle East - and his decision to grant the US permission to use British military bases to launch defensive strikes on Iran.

We'll be bringing you his key lines here, but you can also watch live at the top of this page.

US President Donald Trump has said Keir Starmer "took far too long" to accept a US request to use British military bases for "defensive" strikes on Iranian missile sites.

In an interview with the Telegraph, Trump says the delay in accepting the US request has "probably never happened between our countries before".

Speaking of Starmer, he adds: "It sounds like he was worried about the legality."

The prime minister's official spokesman, asked about Trump's remarks, says Iran striking British interests led to the change in position and he describes the UK and US as "staunch allies".

Nick Johnson
Reporting from RAF Fairford

At just under two miles, RAF Fairford in Gloucestershire - which is used by the US Air Force - has one of the longest runways in the UK.

It’s of a sufficient length to be used by some of the biggest and heaviest American bombers, including the B-52 and B-2 stealth aircraft.

The UK is also roughly halfway between the US East Coast and the Persian Gulf, making it a strategic location for American military aircraft to refuel.

Donald Trump has previously said it may be necessary to use RAF Fairford for US operations in Iran. Prime Minister Keir Starmer has said British military bases would be used for defensive strikes on the country.

There are no planes on the tarmac at RAF Fairford today, but plenty of military-green refuelling trucks positioned alongside the runway.

While it’s quiet at the moment, there’s every chance that could change.

This afternoon, we're expecting to hear from both UK Prime Minister Keir Starmer and US President Donald Trump.

Starmer is set to make a statement on the Middle East in the House of Commons at around 15:30 GMT.

Soon after, at around 16:00 GMT (11:00 ET), we're also expecting an update from Trump as he participates in a Medal of Honor ceremony at the White House.

We'll bring you the news lines here, and you can also watch live by tapping the button at the top of the page.

New video, verified by the Reuters news agency, shows workers evacuating the state-owned Ras Tanura oil refinery in Saudi Arabia.

In the footage - which has been muted - thick plumes of smoke that appear to be billowing from multiple parts of the complex can be seen.

Earlier, the country's energy ministry put out a statement - shared by the Saudi Press Agency - saying a "limited fire" at the plant was now under control.

It also said that the refinery had sustained "minor damage" from falling debris after the interception of "two drones in the refinery's vicinity".

Dharshini David
Deputy economics editor

In a spate of breathtaking moments, the surge in oil and gas prices might appear another - not least as households around the world remain scarred by the spike in energy prices a few years ago.

What could the economics implications be? It depends on how far those prices go - and how long they remain elevated.

But the impact of the current level of those prices suggests the impact could be relatively muted.

Economists reckon that broadly, a sustained rise in oil prices of about 5% adds about 0.1% to inflation in major economies - so the current increase in crude costs would point to a rise of about 0.2% to inflation.

But then there’s gas futures to consider. They are now up more than 40% which, if sustained, may mean a considerable bump to energy bills (albeit not until the summer). Even so, we’re a long way off the peak movements we saw during the war in Ukraine

As it stands, barring a more extensive surge in energy costs, the impact on inflation could be unhelpful - but not disastrous . However, these are early days, and much could change.

Netanyahu tells reporters that the Iranian regime will "threaten all of humanity" if they are able to get nuclear weapons and the means to deliver them.

"So we set out to protect ourselves, but in so doing we protect many others," he says during his visit to Beit Shemesh.

"I want to say a special thanks to our great friend and a great leader of the world Donald Trump in joining us in this great effort to save the world."

Israeli Prime Minister Benjamin Netanyahu is currently speaking to reporters at the site of a fatal Iranian ballistic missile strike on Sunday.

The blast, at Beit Shemesh - between Tel Aviv and Jerusalem - saw nine Israelis killed, including three teenagers.

Ghoncheh Habibiazad
Senior reporter, BBC Persian

Iran state TV Channel Two has confirmed that Mansoureh Khojaste Bagherzadeh, wife of Iran’s Supreme Leader Ali Khamenei, has also been killed “at home”.

Iranian outlets had previously reported that Bagherzadeh was in a coma.

Previously, Iranian media had said that Khamenei’s daughter, grandchild and son-in-law have been killed.

Khamenei and his wife had six children, four sons and two daughters.

Carine Torbey
BBC Arabic correspondent, in Beirut

Earlier, we visited a school in Beirut that, since the very early hours of the morning, has turned into a shelter for the large number of displaced people who fled their houses for fear of being killed by the Israeli military campaign.

We saw people in their pyjamas; others coming with a small bag containing all they could grab as they left their houses in a rush. A few had also brought their pets along.

"I wouldn’t leave them [the pets] behind. They are souls," a woman who left her house in southern Beirut alongside her three children told me.

As we were there, news came of a new Israeli strike. A man commented: "They want to do the same thing they did in Gaza."

A lot of babies and toddlers were in the main court of the school while their parents tried to find an empty room in the building. But the place was filling up very quickly.

A lot of people were asked to check for shelter in other nearby schools.

Image source, Reuters

The United States has urged its citizens in Lebanon to leave the country immediately.

"We urge US citizens not to travel to Lebanon. If you are in the country, depart Lebanon NOW while commercial flight options remain available," the US Embassy in Beirut writes on X.

"The security situation in Lebanon is volatile and unpredictable. Airstrikes have occurred throughout the country, especially in the south, the Beqaa, and parts of Beirut."

Only a few minutes ago, our colleagues in the Lebanese capital reported hearing a large explosion in Dahieh, a stronghold of Iran-affiliated Hezbollah.

Dubai Airports say "a limited resumption" of flights will begin this evening, with a "small number of flights" from Dubai International (DXB) and Dubai World Central – Al Maktoum International (DWC).

But they tell travellers not to travel to the airports unless contacted by their airline with a confirmed departure time.

Emirates airline - based in Dubai - says "we are accommodating customers with earlier bookings as a priority".

Meanwhile, Germany will send planes to evacuate tourists stranded in the Middle East, its foreign minister says.

They will be flown out of Riyadh, Saudi Arabia, and Muscat, Oman, Johann Wadephul tells reporters, according to Reuters.

This morning, UK Foreign Secretary Yvette Cooper said the government is working "immensely hard" to help people return home. She said around 100,000 British citizens have registered their presence with the UK Foreign Office.