WASHINGTON (AP) _ Parting company with one of its closest allies, the United States declined on Tuesday to follow Britain's lead and exchange ambassadors with Libya.

Even to have economic sanctions lifted, Libya must act to stop its support for terrorism and cooperate with the investigation of the bombing of Pan Am Flight 103 in 1988, pay compensation for the 270 people, including 189 Americans, who perished and accept responsibility for the attack, State Department spokesman James P. Rubin said.

Britain announced Monday that it expected to send an ambassador to Libya next month, restoring full diplomatic relations after nearly 16 years.

Foreign Secretary Robin Cook told Parliament Libya had paid compensation for the April 1984 death of London policewoman Yvonne Fletcher, shot by a gunman firing from inside the Libyan Embassy.

Earlier in the year, Libya surrendered two men, allegedly Libyan intelligence agents, for trial next year in the Pan Am bombing over Scotland.

``As far as the British decision is concerned, that's really for the British government to decide,'' Rubin said.

But, the U.S. official said, it was premature for the United States to combine resuming diplomatic relations with Moammar Gadhafi's government in North Africa.

Rubin said Libya's opposition to peacemaking between the Arabs and Israel was ``in and of itself not a reason'' for withholding U.S. recognition from Libya. He said the United States had relations with several governments that do not support the peace process.