(Adds Boucher comments)
By Robert Birsel
ISLAMABAD, June 25 (Reuters) - Pakistan said on Wednesday it would not allow militants to attack Afghanistan from its territory and it would never let foreign troops operate on its soil.
The declaration came after threats from Afghan President Hamid Karzai to send troops into Pakistan to fight Taliban militants he says operate from border sanctuaries, and after 11 Pakistani border soldiers were killed in a U.S. air strike.
"Pakistan will not allow its territory to be used against other countries, especially Afghanistan and under no circumstances will foreign troops be allowed to operate inside Pakistan," the government said in a statement after a top-level security meeting.
Prime Minister Yousaf Raza Gilani presided over the meeting which included federal and provincial government leaders and military and security agency chiefs.
"The meeting unanimously agreed that elimination of terrorism and extremism is the gravest challenge to Pakistan's national security and to fight this menace a multi-pronged strategy will be followed," the government said.
It was the strongest message on militancy yet from a three-month old government that critics say has been preoccupied with internal political wrangling and blind to looming security threats.
The main thrust of the policy would be the political engagement of the people through their elected representatives and tribal elders, together with economic development and "selective use of military force", the government said.
Richard Boucher, U.S. Assistant Secretary of State for South and Central Asian affairs, welcomed the declaration at a hearing on Pakistan before the Senate Foreign Relations Committee:
"We see this as a very important development. It brings together all the proper players...It states very clearly the goals of ending violent extremism, ending the cross border activity and expelling the foreign fighters," he said
The government that emerged from February elections, made up of President Pervez Musharraf's opponents, is trying to end violence through talks with tribal elders in the hope they can press militants in their areas to give up.
But the United States says negotiations and peace deals with militants can give them a free hand to plot attacks and U.S. military commanders in Afghanistan say Taliban attacks launched from Pakistani border sanctuaries have been increasing.
The government said tribal elders would be responsible for expelling foreign militants and for ensuring that militants did not cross the border into Afghanistan.
"All agreements with the tribes ... will be backed by a robust enforcement mechanism" with the government reserving the right to use force, it said.
It did not refer to similar agreements struck under the previous government which failed to curb militant violence and, critics say, enabled the militants to regroup.
Many Pakistanis blame Musharraf's alliance with the United States and his support for the U.S.-led campaign against terrorism for a wave of violence in Pakistan in which hundreds of people have been killed over the past year.
The two main partners in the new coalition government, slain former prime minister Benazir Bhutto's party and that of another former prime minister, Nawaz Sharif, came to power after promising a new approach, including negotiations.
But security has been deteriorating in several parts of the northwest over recent days.
This week, Pakistani Taliban seized a town and killed more than 30 rivals, kidnapped nearly 20 policemen in the strategically important Khyber pass and battled soldiers and police in a northwestern valley where a peace deal was struck last month.
Editing by Sanjeev Miglani