The United States, reeling from the death and destruction wrought by Hurricane Katrina, said Thursday it would accept any offers of assistance, as the world community rallied to its aid.

"We are open to all offers of assistance from other nations, and I would expect we would take people up on offers of assistance when it's necessary," said White House spokesman Scott McClellan.

But asked whether this was a request for foreign aid, McClellan sharply replied: "No."

The signal by the United States, the world's only superpower, marks an extraordinary reversal of roles for the country that is more used to coming to the assistance of others.

Offers -- some merely to show sympathy for an ally in trouble -- streamed in after the United States, the world's biggest single aid donor, said it would be open to assistance even though it was not making an appeal for foreign aid.

The world has watched amazed as the planet's only superpower struggles with the aftermath of Hurricane Katrina, with some saying the chaos has exposed flaws and deep divisions in American society.

World leaders and ordinary citizens have expressed sympathy with the people of the southern United States whose lives were devastated by the hurricane and the flooding that followed.

But many have also been shocked by the images of disorder beamed around the world -- looters roaming the debris-strewn streets and thousands of people gathered in New Orleans waiting for the authorities fail to provide food, water and other aid.

UN Secretary General Kofi Annan on Thursday urged the world to offer assistance to the United States after the devastation wrought by Hurricane Katrina which he described as a "huge disaster".

"The damage is far worse than any of us imagined at first," Annan said in a statement released by his office.

"The American people who have always been the most generous in responding to disasters in other parts of the world have now themselves suffered a grievous blow," he added.

Scenes of chaos -- explosions and fires erupting in New Orleans, looters on the rampage, bodies in the streets, and refugees crammed into a stinking squalor in the city's Superdome -- prompted an outpouring of shock, and sympathy.

"Whatever they ask for, it will be given, from reserves of oil... to any other thing that they may need," European Union foreign policy chief Javier Solana said in Newport Wales, during a meeting of the 25-nation bloc.

The North Atlantic Treaty Organisation chief, Jaap de Hoop Scheffer, said Nato stood ready to contribute.

"Whenever and wherever our Nato partner and important friend -- the United States of America -- asks (for) assistance, Nato stands ready to answer those calls," Scheffer told a press conference during a visit to Sofia.

Among the major allies:

-- The French foreign ministry offered eight aircraft and two ships, with 600 tents and 1,000 camp beds also available at the United States' request.

-- Prime Minister Tony Blair said he had spoken to President George W. Bush, and Britain was ready to help "in any way that we can."

-- German Chancellor Gerhard Schroeder was personally working out the details of a relief package, a government spokesman said. Berlin could provide assistance on water treatment or shelter for people left homeless, a government spokesman said.

-- Japan said offered 200,000 dollars for the American Red Cross and up to 300,000 dollars worth of tents, blankets, power generators and water tanks. Toyota offered five million dollar, Nissan 500,000 dollars.

-- Australia promised 10 million Australian dollars (7.5 million US) through the American Red Cross.

-- Canadian Defence Minister Bill Graham said his country was preparing a package, including an offer of military assets.

-- The Netherlands, a low-lying country that depends on its system of levees, or dams, has offered to send a team of experts to help plan the reconstruction of New Orleans.

More poignant were offers from the needy.

Sri Lanka -- still recovering from the December 26 tsunami which devastated the island's coastlines and killed 31,000 people -- said it had donated 25,000 dollars and asked doctors to help the relief effort.

Somalis, too, offered sympathy.

"New Orleans looks like Mogadishu when the war started," said bus driver Aden Mohamud in Somalia's war-shattered capital.

He said he was troubled by television images that showed most of the some 300,000 desperate people still trapped in New Orleans were black.

"Maybe some whites are also starving but the African Americans are who I have seen," Mohamud said. "I am sorry they are poor like us."