British Prime Minister David Cameron repeated his assertion Tuesday that the release of the Lockerbie bomber was "profoundly misguided."

But he hardened his defense of BP, saying the company -- facing criticism for the Gulf of Mexico disaster -- had nothing to do with the release of Libyan bomber Abdel Baset al Megrahi on compassionate grounds.

Cameron was speaking on National Public Radio in Washington as he prepared to meet U.S. senators angry at alleged links between the release of Megrahi and the award of a lucrative Libyan oil exploration contract to BP.

Megrahi was the only person convicted of the 1988 bombing of a Pan Am passenger jet over the Scottish town of Lockerbie, which left 270 people dead.

Asked what he will say to the senators, he said: "I will say to them that I agree that the decision to release Megrahi was wrong. I said it was wrong at the time. It was the Scottish government that took that decision. They took it after proper process and what they saw as the right, compassionate reasons. I just happen to think it was profoundly misguided."

He added, "He was convicted of the biggest mass murder and in my view he should have died in jail. I said that very, very clearly at the time; that is my view today."

But he hardened his defense of embattled oil giant BP: "Of course BP has got to do everything necessary to cap the oil well, to clean up the spill, to pay compensation. I have met with BP and I know they want to do that and will do that. But let's be clear about who released Megrahi ... it was a government decision in the U.K. It was the wrong decision. It was not the decision of BP -- it was the decision of Scottish ministers."

Cameron will meet with four New York and New Jersey senators -- Kirsten Gillibrand (D-N.Y.), Charles Schumer (D-N.Y.), Frank Lautenberg (D-N.J.) and Robert Menendez (D-N.J.) -- at the British ambassador's residence.

Schumer said in a statement, "We are glad the Prime Minister has agreed to meet with us. We plan to ask him to have the U.K. do a complete investigation and bring Megrahi back to justice."