President Obama, looking to improve ties with America's closest strategic ally, joined British Prime Minister David Cameron in dismissing calls for an investigation into what role BP may have played in releasing the Lockerbie bomber.

The two leaders, in their first formal White House meeting, called each other by their first names, joked about warm beer and untidy children's bedrooms, and spoke warmly of the so-called "special relationship."

Both expressed outrage at the release nearly a year ago of Abdel Baset al-Megrahi from a Scottish prison, but said there is no point in probing whether BP influenced the decision to protect its oil interests in Libya.

"Let us not confuse the oil spill with the Libyan bomber," Cameron said during a short press availability with Obama. "In our meeting we had what we call a 'violent agreement,' which is that releasing the Lockerbie bomber, a mass murderer of 270 people, the largest act of terrorism ever committed in the United Kingdom, was completely wrong."

But Cameron said it was decided by officials in Scotland, saying, "I'm not currently minded that we need to have a U.K.-based inquiry into this."

Obama, under pressure by some Senate Democrats to put the weight of the White House behind a congressional inquiry into what role BP may have played in the matter, also demurred.

"We welcome any additional information that will give us insights and a better understanding of why the decision was made," Obama said. "But the bottom line is, is that we all disagreed with it. It was a bad decision."

Megrahi was the only person convicted in the 1988 bombing of a Pan Am flight over Scotland. Of the 270 people killed in the incident, 189 were Americans.

In August, 2009, the Libyan was released from Scottish prison after serving eight years of a life sentence, because he was said to be in the final stages of prostate cancer and given just months to live.

Greeted at home as a hero, Megrahi is reportedly living in a seaside villa. Conflicting reports have alleged that BP pressured Scottish authorities to release the bomber -- a claim the British government has denied.

BP officials said earlier this month that they pressed the UK government for fast action on a prisoner exchange program, out of concern for the fate of an exploration deal with Libya. But they denied any direct advocacy on behalf of Megrahi.

The Senate Foreign Relations Committee has plans to probe BP's involvement in the matter on its own, and Cameron vowed his government's cooperation with that investigation.

At the same time, Cameron appears to have his own conflict in the matter, with a strong interest in keeping the oil giant viable and operational despite the devastating financial effects of the oil spill.

"BP is an important company to both the British and the American economies. Thousands of jobs on both sides of the Atlantic depend on it," Cameron said. "So it's in the interest of both our countries, as we agreed, that it remains a strong and stable company for the future."