But the NOAA forecast was a reminder that oil gushing from the damaged well, broken up and carried by winds and ocean currents, could threaten a vast area of the US Gulf Coast, including Florida, as well as Cuba and Mexico.

Another uncertain plan

in depth

Representatives of oil giant BP, have also warned that the blown-out deepwater well may not be completely shut off until August as the company scrambles to launch yet another uncertain attempt to contain the spewing oil.

The plan involves cutting out the well head and moving a multi-tonne device called a blow out preventer, and then having a drill ship send down a long-pipe with a nozzle that would suck up the oil coming out.

BP has said that – if successful – the procedure will be able to get only a majority of the oil, not all of it, and the Obama administration said on Sunday that the amount of oil leaking from the ruptured well could increase as much as 20 per cent while efforts were made to cap it.

BP's latest plan, likely to start on Tuesday, comes after its "top kill" manoeuvre to plug the leak failed.

Obama is to hold his first meeting with the commission investigating the disaster [AFP]

The top kill operation, which involved pumping mud into the well - most of which escaped out of the well's damaged riser pipe - was the latest of several failed attempts to plug the leaking well.

Meanwhile on Tuesday, Barack Obama, the US president, is set to hold his first meeting with the leaders of a commission tasked with investigating the spill.

And Eric Holder, the attorney-general, will meet federal prosecutors and state attorneys-general in the city of New Orleans on Tuesday in a prelude to what legal experts believe will be a criminal investigation into the disaster.

In the six weeks since an explosion hit BP's Deepwater Horizon drilling rig, killing 11 workers, the leaking well has spewed an estimated 68 million litres of oil into the Gulf of Mexico.

The crisis, now in its 42nd day, is the worst in US history - exceeding even the Exxon Valdez disaster in 1989 off the Alaska coast.