Sen. Charles Schumer (D-N.Y.) is pressuring the Obama administration to condition recognition of the Libyan rebellion on the Lockerbie bomber's return to prison.

Schumer penned a letter to Secretary of State Hillary Clinton asking that "long term support or recognition of the Libyan opposition movement" be based "on a public, enforceable commitment by the opposition" to send Abdel Basset al-Megrahi, who was freed from Scottish prison in 2009, to the United States for trial before a criminal court.

"This should be straightforward and simple, if you get our support, we get al-Megrahi," Schumer said in a statement. "We are putting American lives on the line, and American taxpayers’ money to use to protect Libyan civilians and, in effect, supporting the rebels so it makes perfect sense to insist that support for their cause is conditioned upon sending al-Megrahi back to prison where he belongs."

Schumer is one of several members of Congress demanding oversight of the U.S. military intervention in Libya, but his effort stands apart for its focus on al-Megrahi, the Libyan who was convicted in Scottish court for the 1982 bombing of Pan Am Flight 103, an attack that left 270 dead.

Schumer's letter came amid reports that the Obama administration authorized covert action to gather information on and assist the Libyan rebellion, and is considering arming their forces.

President Obama has said he wants Libyan leader Moammar Gadhafi gone from power, but lawmakers from both parties have said the West should learn more about the identity of the rebel movement before it puts its whole weight behind it. 

GOP Sen. Lindsey Graham (S.C.) also urged the administration to investigate Gadhafi's role in the Pan Am bombing.

Al-Megrahi was granted his release to Libya in 2009 on compassionate grounds since he was diagnosed with terminal prostate cancer, a move strongly opposed by the U.S. and U.K. governments. His condition has reportedly subsided, leading to even more skepticism of the decision.

New York-area lawmakers have intensely focused on putting al-Megrahi back in prison, since Flight 103 departed from New York City's John F. Kennedy Airport before being brought down over Lockerbie, Scotland.

"The U.S.’s firm commitment to protecting innocent life in Libya should be held into account by any future Libyan government — and the opposition movement that has demonstrated its goal to live in free and accountable Libya must demonstrate its commitment to justice by ensuring that a global terrorist like al-Megrahi lives out his days in prison, not in a luxurious villa," Schumer wrote.