Jay Garner, the retired US general overseeing Iraq's reconstruction, arrived in Baghdad on Monday to see for himself the devastation suffered by the capital.

But in a sign of tensions with Iraqi leaders emerging after the fall of Saddam Hussein, Garner's team said the US did not recognise the authority of an Iraqi who has declared himself governor of Baghdad. And not all Baghdad residents welcomed the US-led team tasked with rebuilding their country.

"What better day in your life can you have than to be able to help somebody else, to help other people, and that is what we intend to do," Garner, head of the Office of Reconstruction and Humanitarian Assistance, said on arrival.

He said his priority was to restore basic services such as water and electricity. Asked what the greatest challenge was, he said: "Everything is the challenge."

At the Yarmuk Hospital in southern Baghdad, Garner was led through dark, dusty corridors littered with broken glass and shown wards stripped by looters of everything except beds.

"What we need to do from this day forward is to give birth to a new system in Iraq," he told doctors at the hospital. "It begins with us working together, but it is hard work and it takes a long time. We will help you as long as you want us to."

But not all were convinced.

"I want to cry, because these are only words," said a doctor who gave her name as Iman. "If they give us anything it is not from their own pockets. It is from our oil," she said.

"Saddam Hussein was an unjust ruler, but maybe one day we could have got rid of him, and not had these foreigners come in to our country."

Garner said his aim was to get the job done and leave as soon as possible but would not be drawn on a timeframe when asked if the work could be completed in 90 days.

"I wouldn't put 90 days as a mark on the wall," he said. "We will be here as long as it takes. We will leave fairly rapidly."

Barbara Bodine, coordinator for central Iraq in the US civil administration, said Washington did not recognise the authority of Mohammed Mohsen al-Zubaidi, who said earlier this month that he had been declared governor of Baghdad.

"We don't really know much about him except that he's declared himself mayor," said Bodine, a former US ambassador to Yemen. "We don't recognise him. There hasn't been a process of selection. Once there's a process, then whomever."

Zubaidi's self-styled deputy, Jawdat al-Obeidi, has said he would represent Iraq at an emergency meeting of the Organisation of Petroleum Exporting Countries starting on Thursday in Vienna. But Bodine said it was unlikely OPEC would accept him.

Garner's initial team of about 19 civilian administrators will swell to about 450 over the next week.

They face an uphill struggle -- Iraqis have criticised US-led forces for failing to restore order, authority, power and water to cities after toppling Saddam's regime.