Security has been stepped up throughout Iraq

Defence Secretary Donald Rumsfeld said this could take at least two years.

"There is no decision to pull out early," Mr Rumsfeld said, despite mounting attacks on the US-led troops.

On Friday, US helicopter gunships killed seven Iraqis near the northern town of Tikrit, suspected of preparing rocket attacks, the US military said.

The US general leading the military operation in Iraq, John Abizaid, has announced that he is moving his headquarters from the US to Qatar.

General Abizaid says forces opposing US-led troops in the country totalled no more than 5,000 - the majority being loyalists of ousted Iraqi leader Saddam Hussein.

Plan change

Beginning a visit to Japan, Mr Rumsfeld said there were no plans for an early US withdrawal from Iraq.

But he said that Iraqis would get political power more quickly than had initially been thought.

"It does not mean that we would physically leave the country any sooner," Mr Rumsfeld said at a US Air Force base on the Pacific island of Guam.

LIKELY TRANSFER SEQUENCE Step 1: Passing power to IGC Step 2: Elections Step 3: Constitution

"There is no question that we have a way to go to find success - and I would describe success as transferring responsibilities of that government to the Iraqi people," he said.

President George W Bush told reporters on Thursday that he had asked his top man in Iraq, Paul Bremer, to come up with strategies for speeding up the transfer of power.

"We want the Iraqis to be more involved in the governance of their country," Mr Bush told reporters at the White House

The old seven-step approach, which included the writing of a constitution, then a referendum on that constitution, elections, and only after that the handing over of sovereignty to an Iraqi Government, has been abandoned.

But the precise details of the new plan to replace it have yet to be worked out, says the BBC's Justin Webb in Washington.

France - which led opposition at the invasion of Iraq - has called for the transfer of power to a representative assembly of Iraqis by the end of 2003.

Security stepped up

After the attack in the southern town of Nasiriya, that killed 18 Italians and nine Iraqis, security has been stepped up across Iraq.

US troops of the First Armoured Division in Baghdad have fired mortars and artillery at a former Republican Guard compound near the international airport.

Codenamed Iron Hammer, this operation represents a far tougher approach by the US, says the BBC's Peter Biles in Baghdad.

More Iraqis have died in guerrilla attacks than coalition troops

In Saddam Hussein's home town of Tikrit, US forces have arrested at least four Iraqis suspected of involvement in last week's downing of a Black Hawk helicopter that killed all six Americans on board.

In Basra - capital of the southern occupation zone - Coalition Provisional Authority (CPA) staff have been confined to their headquarters after the threat of a possible attack.

They were expected to remain confined indoors until Saturday evening.

A spokesman admitted to the BBC that the measures came in response to intelligence following the suicide bomb in Nasiriya - but a specific threat of attack has not been confirmed.

British troops have stepped up patrols, mounting vigorous checks.

UK Foreign Secretary Jack Straw has said more troops will be sent if necessary, while Italian Prime Minister Silvio Berlusconi, another key US ally, has said the attack at Nasiriya will not affect Italian participation in the US-led operation.