The approach of tropical storm Bonnie today forced BP to halt efforts to permanently plug a gushing oil leak in the Gulf of Mexico, sending ships and workers retreating to safety.
Two rigs stopped drilling the relief wells intended to halt the leak for good and prepared to move out of the path of the storm, which was expected to hit the spill area tomorrow with winds of 62-117kph.
Many non-essential workers already have abandoned the spill site, and officials said key ships would likely pull out later today and be gone about two days.
Ships collecting seismic and acoustic data on the capped well and those operating underwater robots that provide a live feed of the wellhead would be the last to leave, and could stay if seas do not become too rough, officials said.
"If we have to evacuate the scene we're probably looking at a very limited window - probably 48 hours," retired coast guard admiral Thad Allen, the top US spill official, told reporters.
BP sealed the leak last week with a tight-fitting containment cap, choking off the flow of oil for the first time since an April 20th rig explosion killed 11 workers and sent crude spewing into the Gulf, soiling coastlines and devastating tourism and fishery industries.
The evacuation could push back BP's mid-August target date for a permanent solution to the leak to late August. But the blown-out well will remain capped during the halt to operations, easing fears the gushing leak would resume.
The evacuation also delayed another potential solution, the launch of a "static kill" operation to pump heavy drilling mud and possibly cement into the well.
BP said workers were securing eight company-operated platforms in the Gulf and preparing for a full evacuation of workers.
The US government said today 28.3 per cent of Gulf oil production and 10.4 per cent of Gulf gas output by all companies had been shut ahead of the fast-moving storm.
Mr Allen said the storm could have benefits and drawbacks for containment efforts. Heavy waves and tidal churn could help break up the oil more quickly, but high winds and waves could drive it deeper into fragile wetlands and coastal areas.
BP's containment efforts have been watched closely by investors because its ultimate costs may hinge on how much oil is determined to have flowed into the Gulf.
Company shares were up about 1.5 per cent in early afternoon trading in New York while the broader market remained flat. BP shares closed relatively flat in London, down 0.3 per cent.
The company's second-quarter results are due on Tuesday. Analysts at Barclays bank said BP could report a loss for the second quarter of $13 billion as it makes provisions of up to $25 billion for the cost of the oil spill - far outweighing an expected 77 per cent jump in underlying profits.
The administrator of a $20 billion fund set up by BP to help compensate spill victims said the fund would not prevent future lawsuits against the company that exceeded that amount.
BP's response to the largest offshore oil spill in US history has been marked by a series of public relations gaffes by top management. Calls have grown for the ouster of Chief Executive Tony Hayward.
President Barack Obama, under political pressure for his handling of the spill, plans to spend the August 14th weekend along the hard-hit Florida Gulf Coast.
Reuters