BP says relief well drilling operation progressing ‘better than expected’

A spokeswoman for the company was quoted as saying it was "ahead of the original schedule of completion in August".

Asked about comments made by Bob Dudley, the man in charge, that finishing by 27 July 2010 was possible, she emphasised the caveats in what he said.

Dudley had explained how completion between 20 and 27 July was possible but only "in a perfect world with no interruptions".

In his interview earlier this week, Dudley had added that such a "perfect case" was threatened by the hurricane season in the region and was "unlikely".

The US National Hurricane Centre had issued a warning in the early hours of yesterday about a tropical depression which had formed in the Gulf of Mexico.

Tropical storms could disrupt efforts to contain oil which had been leaking from the site of the Deepwater Horizon rig since April.

Although the depression was not predicted to become a major hurricane, tropical storm warnings were issued for the Texas and Mexico coastlines.

BP was facing massive clean-up costs and compensation claims as a result of the Gulf of Mexico oil leak.

A spokesperson for BP had repeated Dudley's caveats about whether the relief well could be completed by 27 July 2010, saying such an outcome would only be possible without delays or interruptions caused by hurricanes or unforeseen problems.

The spokesperson also said that as the drilling for the relief well got deeper and closer to the leaking pipe the operation would become "more delicate and technically difficult".

Since the oil started leaking, BP had tried a number of different ways to plug the well, including a failed "top kill" procedure which tried to staunch the flow by pumping huge quantities of mud into the blowouts preventer that sits on the seabed.

The company began drilling for the first of two relief wells on 2 May 2010, and for a second on 16 May 2010;.

Yesterday the US government had asked BP to tell it of any major asset sales or merger deals in advance, as it continued to keep a close eye on the oil giant.

The highly unusual request was made in a letter from the US Department of Justice, dated 23 June 2010. BP said it had yet to respond to the letter.