Taliban fighters seeking to regain power in Afghanistan are taking advantage of a recent peace deal with the Pakistan government to dramatically increase attacks on U.S. and allied forces in eastern and southeastern Afghanistan, several American military officials said Tuesday.

Lt.-Gen. Karl Eikenberry, the top U.S. commander in Afghanistan, said in an interview that Taliban attacks surged by 200 per cent in December, and a U.S. military intelligence officer said that since the peace deal went into effect Sept. 5 the number of attacks in the border area has grown by 300 per cent.

Eikenberry did not explicitly criticize the peace deal with tribal leaders in the border area and he said he is confident that U.S. and NATO forces are going to dominate on the decisive battlefields.

But he predicted, "It's going to be a violent spring," and other officials said it has become commonplace for the Pakistani military at border outposts to turn a blind eye to infiltration of Taliban fighters.

Col. Thomas Collins, the chief spokesmen for U.S. forces in Afghanistan, said the Pakistan peace deal has backfired.

"The enemy is taking advantage of that agreement to launch attacks into Afghanistan," Collins said.

Eikenberry spoke to a group of U.S. reporters travelling with Defence Secretary Robert Gates, who was receiving closed-door briefings from military officials on the resurgence of the Taliban in recent months. Gates was accompanied by Marine Gen. Peter Pace, chairman of the Joint Chiefs of Staff.

Gates has publicly expressed concern that a resurgent Taliban could put areas of Afghanistan in danger of reverting to a haven for terrorists. U.S. forces invaded Afghanistan in October 2001 to oust the Taliban, and although gains have been made to stabilize the country, the Taliban has recently made inroads.

"The enemy does use both sides of the border, inside Pakistan as well," with senior Taliban leaders directing insurgent operations in some cases from sanctuaries on the Pakistan side, Eikenberry said.

Other U.S. military officers who briefed reporters on condition of anonymity because the information included sensitive intelligence, painted an even bleaker picture of the results of the September peace deal, which the Pakistan government portrayed as a vehicle for assisting U.S. efforts in Afghanistan.

U.S. officials recently gained firsthand evidence that Pakistani forces at a border control point opposite Afghanistan's Khost province turned a blind eye to infiltration of a substantial number of Taliban fighters. U.S. troops at a base known as Forward Operating Base Tillman urged the Pakistanis to block the infiltrating  fighters but nothing was done, one U.S. military intelligence officer said.

"This is common," another intelligence officer said.

Canada has more than 2,000 soldiers in the southern province of Kandahar. Forty-four soldiers and one diplomat have died since the mission started in 2002.

Earlier this month, Foreign Affairs Minister Peter MacKay promised to raise the border issue with Pakistan President Pervez Musharraf during a visit to the country.