A US government panel is to question BP's US chief over the Gulf oil disaster amid damning accusations the firm took shortcuts.

Lamar McKay has been called to testify along with heads of other oil companies about the safety of deepwater drilling.

Congressmen have suggested in a letter to BP that the company took decisions which raised the risk of a disaster.

US President Barack Obama is due to make a speech to the nation on the spill.

He is expected to outline the next steps his administration will take when he appears on prime-time TV on Tuesday evening.

The president has been touring Gulf states affected by the leak, which he has likened to the 9/11 attacks in terms of its impact.

Oil has been spewing into the Gulf of Mexico since a drilling rig leased by BP exploded and sank on 20 April with the loss of 11 lives.

The US Coast Guard estimates that about 35,000 barrels escape each day.

A cap placed by BP on the damaged oil well earlier this month is now said to be collecting about 15,000 barrels daily.

'Nightmare well'
 
Mr McKay is due to attend the hearing of the House of Representatives committee on energy and environment along with senior officials from other oil companies.

After they testified before the Senate about the disaster last month, President Obama described the hearing as a "ridiculous spectacle".

He talked of "executives of BP and Transocean and Halliburton falling over each other to point the finger of blame at somebody else".

While the theme of Tuesday's hearing is deepwater drilling in general, BP chief executive Tony Hayward will face a separate House hearing on Thursday devoted to the Deepwater Horizon disaster.

Congressmen Henry Waxman and Bart Stupak sent Mr Hayward a letter on Sunday in which they set out technical questions they expect him to answer.

The letter quotes internal communications between BP engineers before the disaster in which the site is described as a "nightmare well" just six days before the disaster.

'Carelessness and complacency'
 
At issue were the choice for the design of the well, preparations for and tests of the cement job, and assurances that the well was properly sealed on the top.

Among other things, BP apparently rejected advice of a subcontractor, Halliburton Inc, in preparing for a cementing job to close up the well.

BP rejected Halliburton's recommendation to use 21 centralisers to make sure the casing ran down the centre of the well bore. Instead, BP used six.

In an e-mail on 16 April, a BP official involved in the decisions explained: "It will take 10 hours to install them. I do not like this."

Later on the same day, another official recognised the risks of proceeding with insufficient centralisers but added: "Who cares, it's done, end of story, will probably be fine."

"It appears that BP repeatedly chose risky procedures in order to reduce costs and save time and made minimal efforts to contain the added risk," the congressmen write.

"If this is what happened, BP's carelessness and complacency have inflicted a heavy toll on the Gulf, its inhabitants, and the workers on the rig," they say.

During his televised address, Mr Obama will announce new steps to restore the Gulf Coast ecosystem, according to a senior administration official who spoke to the Associated Press news agency on condition of anonymity.

Source BBC