President Hamid Karzai criticized Pakistan's plan to mine and fence its border with Afghanistan, saying Thursday that it will separate families but not prevent terrorism.

Karzai's remarks came two days after Pakistan said it would plant land mines and build a fence on parts of its 1,510-mile frontier with Afghanistan.

The Pakistani move was an effort to fend off criticism it does too little to stop Taliban and Al Qaeda guerrillas from crossing the border. Pakistan has also said it will send unspecified military reinforcements to the frontier, joining about 80,000 soldiers already in the country's northwestern tribal regions.

Still, relations have been souring between Afghanistan and Pakistan, which are key U.S. allies in its war on terror groups.

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Karzai said terrorists will still find a way to cross the border to attack in Afghanistan.

"Laying of mines or fencing the border will only separate people, families from each other," he told a news conference. "Rather than helping, it will cause people difficulty in movement, in trade."

The frontier region is inhabited on both sides by Pashtun tribespeople who travel freely across the border. As a result, Pakistan is also likely to draw complaints from its own people.

Karzai said that rather than building a fence, officials must remove the training centers used by terrorists and go after their sources of funding and equipment, steps the Afghan leader often calls for without mentioning the name of his neighboring country.

"If we want to prevent terrorism from crossing the border into Afghanistan, if we want to prevent terrorism as a whole, forever, eradicate them, defeat them, then we must remove their sanctuaries," Karzai said.

Afghan and Western officials contend militants train in Pakistan and then launch attacks in Afghanistan, but the Islamabad government insists it does all it can to stop them. Taliban-led insurgents have stepped up attacks in Afghanistan over the past year, triggering the worst violence since a U.S.-led coalition ousted the hardline regime five years ago.

Mines are deeply unpopular in Afghanistan, where thousands of its civilians have been killed or maimed by mines planted during 25 years of war here.

"We have suffered, and we are very much for the removal, prevention of mines," Karzai said.

U.N. officials on Wednesday criticized Pakistan's plan, saying it would add to civilian casualties.

Fresh evidence of the danger of buried mines came Thursday when officials announced one British soldier was killed and three were wounded by an explosion that caused their NATO vehicle to crash.

The bomb hit a reconnaissance patrol in southern Helmand province on Wednesday, a statement from the International Security Assistance Force said.

Lt. Col. Andy Price told Britain's Sky News that the explosion could have been caused by an old mine from past wars. He said it was unlikely the British soldiers were targeted because the explosion went off "in the middle of the desert."

Pakistan and Afghanistan have an ongoing dispute over the demarcation of their rugged, joint border, but Pakistani Foreign Secretary Riaz Mohammed Khan said his country would be acting on its own territory and did not need Afghan consent for the mines and the fence. Pakistan did not say when or where work would start.

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