US forces continue to patrol Iraq in force

His comments - a day after two US soldiers were killed in separate attacks - were more measured than earlier this month when he seemed to challenge Iraqi militants to "Bring them on".

America's war commander in Iraq, General Tommy Franks, said on Thursday that troops might have to remain on the ground for up to four years.

Efforts to create civilian authorities received a boost however when Britain's top representative in Iraq, John Sawyers, announced a governing council of Iraqis could be up and running within a week.

Whether that means two years or four years, I don't know General Tommy Franks

"There is no question that we have got a security issue in Iraq and we've got to deal with it person by person - we're going to have to remain tough," said Mr Bush in Botswana, on the latest stage of his southern Africa tour.

Mr Bush blamed the continuing attacks on US troops on "apologists for Saddam Hussein" and insisted the US was making "steady progress" in establishing security and rebuilding the country.

The Pentagon has reported the deaths of 65 American service personnel - many of them as a result of hostile fire - in Iraq since 1 May when Mr Bush declared that major combat was over.

On Wednesday alone:

• One soldier was killed and another injured in a grenade attack on a convoy near Tikrit

• A US soldier was shot dead near Mahmudiya in an attack on his convoy

• A third soldier died in a "non-hostile gunshot incident" in Iraq

US troops based in Ramadi, about 100 kilometres (60 miles) west of Baghdad, have also come under mortar fire at least five times since Wednesday evening but there are no reports of injuries.

BBC correspondent Peter Greste in Baghdad says that Ramadi and Mahmudiya are both regarded as former Saddam strongholds

A recent audio tape purporting to come from Saddam himself urged Iraqis to continue attacks on coalition troops in the country.

'Iraqi voice'

General Franks told the US Congress that he believed troops would remain in Iraq for some years.

"Whether that means two years or four years, I don't know," he said in testimony ahead of his retirement from the military.

The US hopes to recruit local security forces

The BBC's Pentagon correspondent, Nick Childs, says there is growing public disquiet in the US, and not least in Congress, over how many troops will have to remain in Iraq for how long and at what risk.

General Franks also suggested that Washington would have to keep around 150,000 troops in Iraq for the foreseeable future.

John Sawyers, Britain's most senior representative in Iraq, has predicted that a new Iraqi Council he expects to see functioning from next week onwards will give a sense of hope and a voice to the Iraqi people.

The Council will have around 25 members, drawn from across Iraqi society with a Shia Muslim majority.