Richard Holbrooke’s struggle to become US Ambassador to the United Nations ended Wednesday when he was sworn in to his new post in a brief ceremony at the US Mission here.

Holbrooke, who was confirmed to his post only after a 14-month fight in the Republican-led Senate, intended to travel immediately to Kosovo, among other Balkan hot spots, to meet UN officials and gather information on recent events there.

The new US ambassador planned to leave Friday for Pristina, the capital of Kosovo, as well as visits to Albania, Macedonia and Bosnia-Hercegovina.

Although he was sworn in to his duties Wednesday, Holbrooke officially takes over his post only after presenting his diplomatic credentials to UN Secretary-General Kofi Annan, which he is expected to do in early September.

US officials highlighted Holbrooke’s trip to the Balkans as a sign of the importance Washington intended to place on UN efforts in the region.

Holbrooke had underscored that “Kosovo, and peace and implementation in Kosovo and throughout the Balkans, and Bosnia as well, is a major test case for the United Nations,” said US State Department spokesman James Foley.

The new US ambassador can boast considerable expertise in dealing with Balkans crisis, including his decisive role in negotiating the 1995 Dayton Peace Accords which ended the war in Bosnia.

Over the years he negotiated repeatedly with Yugoslav President Slobodan Milosevic but will not do so on this trip, aides said.

They said that Holbrooke would not hold any talks with indicted war criminals – a pointed reference to Milosevic’s indictment in June by the UN tribunal that deals with the former Yugoslavia.

Holbrooke’s appointment in some ways was as hard-fought as his diplomatic successes in the Balkans. Named by US President Bill Clinton in 1998 to succeed Ambassador Bill Richardson – now the US energy secretary – Holbrooke faced months of ethics investigations, and opposition by several Republican senators.

Those problems led to months of delay before the senate finally voted on his nomination in early August. Four separate senators had placed “holds” on any vote, most of them unrelated to Holbrooke and concerned other disputes between the Senate and the White House.

Holbrooke’s troubles have hardly ended with his appointment, according to politicval observers.

With only 18 months to go until Clinton’s presidency ends, Holbrooke must now deal with a United Nations that increasingly has been at odds with the United States over Washington’s 1.6 billion dollars in UN dues, much of it consisting of arrears to UN peacekeeping costs.

Officials here calculated that, unless Washington paid more than 350 million dollars by December, the United States could lose its vote in the 185-member General Assembly.

Marc Theissen, spokesman for Jesse Helms – the rightwing chairman of the Senate Foreign Relations Committee – said that the Senate had accepted a bill which would pay back what Washington owed, but with strict conditions for UN reform.

Among those conditions is a requirement that the United States in the future should only pay 20 percent of UN yearly costs – a decrease from the 25 percent that Washington presently is assessed. UN officials said that other member states were unlikely to accept such a condition.

In any case, Theissen acknowledged, Republicans in Congress may still attempt to attach language to the UN dues bill which would restrict US funding for groups which lobby for changes in abortion policies abroad. Clinton vetoed a previous dues-repayment measure after the abortion restrictions were attached.

Nor are Washington’s problems at the United Nations simply the result of unpaid dues.

A series of unilateral actions by the United States – including air strikes along with British forces on Iraq since December – angered nations which did not want any weakening of the UN Security Council’s role in resolving international disputes.

The Council has been at odds on Iraq since the attacks began and that dispute – together with the future of Kosovo, the recent conflict in central Africa and the peace process in East Timor – is expected to dominate the Council’s agenda next month as Holbrooke settles into his new post.