NEW YORK, Sept 23 (Reuters) - Afghanistan's President Hamid Karzai expressed surprise on Tuesday at comments by his defense minister that Pakistan and Afghanistan were discussing a possible joint border force, but said he would support it. Afghan Defense Minister Abdul Rahim Wardak said in Washington on Monday that the force, to include U.S. troops, would combat Taliban and al Qaeda insurgents who shelter in Pakistan's tribal areas along the border with Afghanistan. The minister said the Afghan government had discussed the task force with Pakistani officials within the past few weeks. Asked about the proposed force during a visit to New York, Karzai said it was the first he had heard of it. "I've heard of a joint border monitoring mechanism that we would monitor the border between the two countries, jointly through a tripartite mechanism where Pakistani officers and Afghan officers would have posts checking the cross-border activity," he said at a meeting of the Asia Society. "Monitor yes, but a force to act together on two sides of the border is a new idea, but a welcome idea. Well, I'll back it," he said. Navy Adm. Mike Mullen, chairman of the U.S. Joint Chiefs of Staff, said on Monday he had not heard any details about the Afghan defense minister's proposal, but that any effort to improve security in the border area was welcome. Militants operating in Pakistan's tribal region now pose the biggest threat to U.S. security and to the future of Pakistan's new civilian government, U.S. Defense Secretary Robert Gates said in Washington on Tuesday. The Taliban, fighting to topple Karzai's government, use the remote region to launch attacks in Afghanistan. Violence in Afghanistan this year is at its worst since the 2001 invasion by U.S.-led coalition forces, with some 3,000 people killed. (Reporting by Daniel Bases; writing by Ross Colvin; editing by Mohammad Zargham)
REFILE - CORRECTING DAY OF SUICIDE CAR BOMB BLAST Debris of a suicide car bomb is seen on the road next to a German military convoy after a blast in Kunduz ...
