The threat posed to Haiti by the cholera outbreak has been magnified by the failure of the United States and other rich countries to deliver promised reconstruction funding quickly enough, it was claimed Monday.

Health officials and aid workers in the Caribbean country were fighting yesterday to prevent the illness spreading to an estimated 1.3?million people living in "tent cities" around the capital, Port-au-Prince.

Over the past week, 259 Haitians have died and 3,342 have been admitted to hospital after being infected by the waterborne disease, which thrives on unsanitary living conditions. Five cases have been confirmed in the capital.

The World Health Organization said yesterday that it was "too early to tell" whether the outbreak was over or if it could yet exploit the poor sanitation and ramshackle conditions in the tents, which are home to people displaced by a devastating earthquake in January, which killed 300,000 people.

Experts said that efforts to rebuild the city had been hindered by "indefensible" delays to the release of billions of pounds in reconstruction money pledged by world leaders seven months ago.

Only about $745 million (Cdn) of the $5.45 billion (Cdn) promised in March for 2010-11 has been delivered, including none of the $1.1 billion (Cdn) pledged from the United States by Hillary Clinton, the U.S. Secretary of State.

Mark Weisbrot, of the Centre for Economic and Policy Research, in Washington, said political in-fighting in the U.S. had blocked the funds being released and deterred other countries from promptly delivering their own money. "It is indefensible that 10 months after the earthquake so many people are still living in temporary shelter," he said. "This is a result of the international failure to achieve even the most basic reconstruction."

John Simon, a former senior U.S. diplomat, said the delay "has potentially impeded the steps that could have been taken to help Haiti come back from something like cholera".

It took four months of bureaucratic debate before the $1.1 billion (Cdn) in aid was approved by the U.S. Congress and signed by President Barack Obama at the end of July. A further three months have passed, with funds still held up in Washington while Mrs Clinton's officials negotiate with members of congressional committees over how the money could be spent.

Many in the U.S., including Bill Clinton, the former president who is now co-chairman of the commission overseeing Haiti's reconstruction, have heaped blame for the delays on Tom Coburn, a Republican senator. Mr Coburn has held up the authorization of some aid spending by objecting to a minor provision in legislation. He in turn has blamed Mrs Clinton for the delays.