The first US ambassador to Libya in three decades arrived in Tripoli today, in a further sign of the two nations' improving ties.

Gene Cretz, a career US diplomat whose foreign postings have included Tel Aviv, Damascus, Cairo, Islamabad, New Delhi, and Beijing, said he would strive to broaden links between Tripoli and Washington.

"I'm happy to be in Libya," he told reporters on his arrival at Tripoli airport, naming business and tourism among his priorities for expanded cooperation.

US-Libyan ties have improved dramatically since Libya's December 2003 decision to abandon the pursuit of weapons of mass destruction and the subsequent resolution of disputes over bombings that Washington long blamed on Libya.

US officials said the last big obstacle to normal ties was removed when Libya in October paid $1.5 billion into a fund to settle claims by the families of US citizens killed in the 1988 bombing of Pan Am flight 103 over Lockerbie, Scotland, the 1986 attack on a West Berlin disco and other such incidents.

After Libyan leader Muammar Gaddafi seized power in a 1969 coup, US-Libyan ties became increasingly strained because of his support for what the United States regarded as international terrorism.

The United States withdrew its ambassador from Tripoli in 1972 and all US diplomats left after a mob attacked and set fire to the US Embassy in 1979.

The two countries re-opened lower-level missions in each other's capitals in 2004 and upgraded them to full embassies in 2006.