Lebanon's president appointed a staunchly pro-Syrian politician, Omar Karami, as prime minister on Thursday, asking him to form the next government in a move that consolidates Syria's hold on Lebanese politics.

Karami, 70, replaces Rafiq Hariri, a billionaire who has had a long rivalry with President Emile Lahoud, a close ally of Syria. Hariri had said he would not continue as prime minister in the new government.

The shake-up came as the United Nations increased the pressure on Syria to end its long domination of Lebanon. In defiance of the U.N. Security Council, Lebanon's parliament recently extended Lahoud's six-year term, which was due to expire in November, by three years.

The issue has divided Lebanon's leadership, creating the nation's worst political crisis since the end of the 1975-90 civil war, and put the country and Syria in confrontation with the United States and France at the United Nations. Syria has 14,000 troops in Lebanon.

Hariri, who enjoys wide-ranging international contacts, was seen as less dependent on Syria than many other politicians. Analysts said his departure cleared the field for a Lebanese government whose ministers are all loyal to Syria.

Lahoud named Karami after polling legislators, according to a statement read by Lahoud's spokesman, Rafiq Shalala. But the appointment was marred by a boycott by nearly a quarter of the legislature -- lawmakers opposed to Syrian domination of their country.

An informal poll of legislators indicated that Karami, who was prime minister in 1990-92, had the support of at least 71 of the parliament's 128 members.

This week the Security Council repeated its appeal to Syria to stop interfering in Lebanese politics and withdraw its army from Lebanon.