Tony Blair has returned from a meeting with US president George W Bush resolute on taking action over Iraq but facing mounting opposition at home.

The prime minister said he and the president had developed a "shared strategy" based on a determination that the country's weapons of mass destruction must be destroyed.

Iraqi cadets are preparing for possible action (AP)

He will use a speech to the Trades Union Congress on Tuesday to argue that while the United Nations should deal with the issue, Saddam Hussein cannot be allowed to flout its resolutions "year after year, after year".

"We have a total determination to deal with this issue. But we do want to deal with it on the basis of the broadest possible international support," said Mr Blair.

"I think what people have been worried about is: are we simply going to go off without any consultation or discussion with allies? That is not the case."

He is planning to brief senior MPs over the coming weeks but many Labour politicians are yet to be convinced of the case for military action.

We cannot drift into military action without there being a very clear and overriding case for that action

Tony Lloyd Labour MP

"We need clearly to have far greater evidence in relation to the existing threat," said Labour MP Donald Anderson, chairman of the Foreign Affairs Select Committee.

His concern was echoed by ex-foreign office minister Tony Lloyd who said that any decisions had to be taken by parliament.

"I think we are a long way from being convinced, not just me and not just my parliamentary colleagues, but millions of people in Britain, for the reason that the dossier that we were promised is not yet with us," he said.

Tam Dalyell, who is also the father of the House of Commons, said nothing Mr Blair had said so far had convinced him a pre-emptive strike was necessary.

And he called for an emergency parliamentary debate on Iraq as soon as possible.

Union opposition

Mr Blair will also face a rough ride on the issue at the TUC conference, which opens in Blackpool on Monday.

The two rail unions, Aslef and the RMT, have tabled a motion to oppose action in Iraq.

GMB leader John Edmonds said the overwhelming feeling of TUC delegates was that war should not be contemplated without total UN support.

"War against a member state in the 21st century should only be a matter of last resort, sanctified and sanctioned by the UN."

Iraq today is not a threat to its neighbours and is not acting in a manner which threatens anyone outside its own borders

Scott Ritter

A former UN arms inspector has also expressed alarm at the prospect of military action.

Scott Ritter addressed the Baghdad parliament on Sunday, saying it would be a "historical mistake" for Iraq to be attacked by the US.

He said the only way to avoid war was for Iraq to allow UN weapons inspectors back in and give them unfettered access.

President Bush is due to address the United Nations on Thursday in a speech US officials say will demand fast, decisive action from the international body.

In an interview with the BBC's Breakfast with Frost programme, US Secretary of State Colin Powell admitted differences remained within the Bush administration over whether to launch a military attack on Iraq.

He said President George W Bush's advisers "all have lots of views and we all communicate in different ways," adding that the president was "examining all our options - political, diplomatic, military".

Weapons dossier

Both the US and UK governments say they have proof Iraq has biological and chemical weapons and the potential for a nuclear capability.

Mr Blair has promised to publish a dossier showing this in a few weeks' time.

He arrived back in the UK on Sunday to Aberdeen airport en route to a scheduled meeting with the Queen at her Highland residence, Balmoral.

He is due to visit Moscow in the next few weeks to brief Russian premier Vladimir Putin who has already said he has "serious doubts" about military action against Iraq.