The White House Monday said President Barack Obama had no plans to meet Libyan leader Moammar Gadhafi at the United Nations next month, but declined to rule out a chance encounter.

Even a passing greeting between Obama and Gadhafi would be a politically tense moment, as a backlash mounts in the United States at the hero's welcome granted by Libya to freed Lockerbie bomber Abdelbaset Ali Mohmet al-Megrahi.

Obama is due to attend his first United Nations General Assembly meeting in September and Gadhafi is also expected to address the session, fueling speculation they could meet in the next step of improving U.S.-Libyan relations.

"This year Kadhafi is the head of the General Assembly, and so I assume that at some point they'll run into each other," White House deputy spokesman Bill Burton said at Martha's Vineyard, a well-heeled east coast resort where Obama is on vacation.

"But there's no scheduled meeting and no plans to schedule one."

Scotland's release of terminally ill Megrahi on compassionate grounds provoked fury in the United States among top political leaders and relatives of those who were killed when a Pan Am jet was blown out of the sky over Lockerbie, in December 1988.

Independent Sen. Joseph Lieberman on Sunday called for an independent investigation of Scotland's decision to free the Lockerbie bomber, expressing concern that British interest in Libyan oil may have played a role.

Sen. Ben Cardin, a Democrat, also raised questions about the freeing of Megrahi on compassionate grounds.

Both Lieberman and Cardin said on CNN that Libya's celebratory homecoming for the former intelligence officer should have consequences.

Lieberman called it "a real setback for the anti-terrorist cause and takes our relations with Libya back to where they were for too long — a bad place."

Obama on Friday slammed the welcome granted to the Lockerbie bomber as "highly objectionable" and U.S. officials warned the conduct of the Tripoli government in coming days would have an impact in improved diplomatic relations.

Copyright AFP 2009