UK troops in Afghanistan beyond 3 years -general

LONDON, Sep 6 (Reuters) British troops will probably have to stay in Afghanistan beyond their three-year mission, the new head of Britain's army said.

Asked whether he thought his troops, who entered southern Afghanistan this year, would stay beyond the three years announced by the government, General Sir Richard Dannatt said: ''We have undertaken a mission that is pretty comprehensive.'' ''Security may take longer than the three years currently funded for,'' Dannatt said. ''It is a decades-long enduring relationship with southern Afghanistan. I fully anticipate we will be there for longer. How long, I don't know.'' He was meeting a group of journalists after taking over as Chief of the General Staff from Sir Mike Jackson.

British troops arrived in southern Afghanistan as part of an expanding NATO peacekeeping force. They have quickly become engaged in unexpectedly heavy fighting with Taliban guerrillas.

British forces suffered their largest single-day death toll on Saturday when a spy plane crashed killing 14 military personnel onboard.

Critics accuse the government of failing to send enough troops to pacify Helmand province, a vast territory that produces a third of the world's heroin, and has not had a large international presence since the Taliban fell in 2001.

Dannatt acknowledged the army was ''running hot'' -- under strain -- with thousands of soldiers deployed in Iraq and Afghanistan, but said it was able to cope with the extra strain.

He said the Taliban were proving to be a tougher enemy than had initially been anticipated but insisted his troops would emerge triumphant.

''It is taking us longer to try to establish a secure environment.'' REUTERS DH PM0500