WASHINGTON, Jan 19: US President George W Bush has nominated career diplomat William Wood as the new US ambassador to Afghanistan, the White House announced on Friday. Mr Wood, 56, is currently the US ambassador to Colombia. He will replace Ronald Neumann, who has served in Kabul since July 2005.

Mr Wood's appointment must be confirmed by the Senate.

A former American negotiator at the United Nations, Mr Wood has spent most of his career in the diplomatic corps. As the US envoy in Bogotá, he helped Colombia's government fight a domestic insurgent group and drug traffickers.

If the Senate approves his nomination, Mr Wood will move to another US ally fighting a guerilla war and a booming illegal drug trade.

The United States is considering sending more troops to stem a resurgence of the Taliban militia, ousted from power in a US-led offensive in 2001.

Bloodshed in Afghanistan last year returned to levels not seen since the fall of the Taliban. Some 4,000 people are believed to have died in the insurgency in 2006 -- about a quarter of them civilians.

Of the 20,000 US troops in Afghanistan, around half operate under the Nato umbrella.