Libya has formally accepted responsibility for the 1988 bombing of a U.S. airliner over Lockerbie, Scotland in a letter submitted to the president of the U.N. Security Council on Friday.

In the letter, Libya renounces terrorism, pledges cooperation in future Lockerbie investigations and agrees to pay "appropriate compensation" into a fund for families of the victims of Pan Am Flight 103. It also says it will cooperate in the international fight against terrorism.

The United States and Britain now say they will not oppose lifting U.N. sanctions on the North African country. However, one senior Bush administration official said the United States may abstain in the vote as a sign of continuing concern about Libya's behavior.

U.S. officials also say that U.S. economic sanctions will remain in "full force" because of concerns over Libya's human rights record and its pursuit of weapons of mass destruction.

A vote on lifting the U.N. sanctions is expected next week.

Libya has agreed to pay $2.7 billion to the families of the Pan Am victims. If the sanctions are lifted, U.S. officials say the families will receive the first $4 million of what could eventually be $10 million in Libyan compensation for each person killed. The remaining $6 million for each victim would not be paid unless U.S. sanctions against Libya are also lifted and the country is removed from the U.S. list of state sponsors of terrorism.

However, France has threatened to exercise its veto in the U.N. vote because Libya paid only $33 million to the families of 170 victims of a 1989 bombing of a French (UTA) airliner over Niger.

U.S. officials, and some of the relatives of the victims of Pan Am Flight 103, expressed annoyance or worse over the French veto threat.

Secretary of State Colin Powell has urged French Foreign Minister Dominique de Villepin not to stand in the way of a Lockerbie agreement.