PRISTINA, Oct 7, 2008 (AFP) - Defence Secretary Robert Gates on Tuesday became the most senior US official to visit Kosovo since it declared independence from Serbia in February, on a trip likely to anger chief Serbia and its ally Russia.

'No secretary of defence has been there since 2001 and I want to let the men and women serving there know we haven't forgotten them and how important they are,' Gates said before touching down in Pristina.

He was to hold meetings with Kosovo's President Fatmir Sejdiu and Prime Minister Hashim Thaci, and General Giuseppe Emilio Gay of Italy, commander of NATO's 16,000 peacekeepers.

The United States has 1,500 troops deployed in Kosovo as part of the KFOR force and Gates gave an assurance that American soldiers would remain there at least until November 2009.

'The next rotation I think will take us until November next year,' Gates said on the plane ahead of the visit which is seen as a reaffirmation by US support for Kosovo's fledgling independence.

US President George W. Bush promised Sejdiu and Thaci in July that he would try to convince more nations to formally recognise Kosovo. The US president expressed support for Kosovo's efforts to join the NATO alliance and the European Union.

More than 40 countries, including most of the European Union's 27 members, have recognized Kosovo's February 17 declaration of independence from Serbia, which along with Russia fiercely opposed the move.

After Kosovo, Gates heads on to Macedonia, a country with ambitions of joining the North Atlantic Treaty Organisation (NATO), before a meeting of the alliance in Hungary on Thursday and Friday.

NATO's extension eastwards, a source of friction with Russia, is likely to figure prominently in Gates's talks in addition to the war effort in Afghanistan.

The NATO meeting is set to discuss relations with Russia, which hit a post-Cold War low point with the Russia-Georgia war in August.

About 90 percent of Kosovo's two million population is ethnic Albanian. A large part of the Serb minority lives in the north and rejects Kosovo's independence.

Defiant Kosovo Serbs held municipal and legislative elections in May at the same time as elections in Serbia and there have been outbreaks of violence since the declaration of independence.