UPDATE 3-Suicide car-bomber kills 27 in Pakistan

(Adds Pakistani Taliban claim of responsibility and byline)

By Mohammad Hashim

KOHAT, Pakistan, April 18 (Reuters) - A suicide car-bomber rammed a Pakistani military convoy on Saturday, killing 25 soldiers and police, and two passers-by, police said.

About 65 people were wounded. Pakistani Taliban claimed responsibility for the attack near Kohat, 190 km (120 miles) west of Islamabad.

"The bomber was driving a pick-up truck which he rammed into a convoy passing by a security checkpost," said senior police officer Fareed Khan in the northwestern town of Kohat.

Khan said the death toll could rise because at least seven out of the 65 wounded were said to be in a critical condition. About eight vehicles in the convoy were destroyed.

President Asif Ali Zardari told aid donors on Friday he would step up the fight against militants and said defeat for nuclear-armed Pakistan would be a defeat for the world.

His nation is a vital U.S. ally in its efforts to stabilise Afghanistan.

A spokesman for Pakistani Taliban chief Baitullah Mehsud said militants would continue its attacks on security forces.