The US government is to allow 13 companies to resume deepwater drilling without any additional environmental scrutiny just months after saying it would require strict reviews in the wake of the BP oil spill in the Gulf of Mexico.
The Obama administration said it was not breaking its promise to require environmental reviews because the 13 companies - which include Chevron USA and Shell Offshore - had already started drilling the wells without detailed environmental studies.
Drilling was suspended last year when a moratorium was imposed following the BP spill. The ban was lifted in October but drilling has not yet resumed in waters deeper than 500ft in the Gulf of Mexico.
US officials said the 13 companies must comply with new policies and rules before resuming activity at 16 Gulf of Mexico wells. All but three are exploratory wells - the same type BP was drilling when the blowout of the Deepwater Horizon rig occurred. The April 20 explosion killed 11 workers and set off the worst offshore oil spill in US history.
Michael Bromwich, director of the Bureau of Ocean Energy Management, Regulation and Enforcement, said: ""For those companies that were in the midst of operations at the time of the deepwater suspensions (last spring), this notification is a significant step toward resuming their permitted activity."
Mr Bromwich stressed the move was not a reversal of its previous plans not to grant waivers known as categorical exclusions for deepwater projects. Instead, officials claimed the action as a sort of grandfather clause that applies only to companies that had already begun drilling before the BP blowout.
But William Snape, senior counsel for the Centre for Biological Diversity, an environmental group, called the announcement "another sad chapter in agency denial that anything is wrong".
He said Mr Bromwich and his boss, Interior Secretary Ken Salazar, seem to want dangerous oil and gas drilling to go on in the Gulf and Alaska "without any meaningful public scientific review of the risks learned from the BP disaster."
Government officials have been under pressure from the oil industry, Gulf state leaders and congressional Republicans to speed up drilling in the Gulf of Mexico, which has come to a near halt since the moratorium on deepwater drilling was imposed last spring.
A federal report said the moratorium probably caused a temporary loss of 8,000 to 12,000 jobs in the Gulf region.