The United States warned Pakistan against negotiating an agreement with militants along its border with Afghanistan, saying a deal might allow them to plot attacks in Pakistan and abroad.

The Bush administration is worried such an agreement, if pursued by Pakistan's newly elected government, would give the militants a free hand in Pakistan's tribal areas, which have long operated outside the central government's full control.

Al Qaeda members as well as Taliban militants are believed to have taken refuge in North and South Waziristan - part of Pakistan's Federally Administered Tribal Areas (FATA) - after US-led forces ousted the Taliban in Afghanistan in 2001.

Al Qaeda leader Osama bin Laden masterminded the September 11 attacks from Afghanistan, where he was sheltered by the Taliban regime, and he is believed to be hiding somewhere along the Afghan-Pakistan border.

Speaking at a congressional hearing, US Deputy Secretary of State John Negroponte voiced the US government's misgivings about the possibility of Pakistan striking agreements with tribal militants.

A previous deal reached by Pakistani President Pervez Musharraf in 2006 was abandoned. Musharraf's allies lost February parliamentary elections, bringing a new coalition government to power.

"Are we concerned about the possibility of negotiations between the government or elements of the government and these extremist groups up there ... yes," Negroponte said.

Fiercely independent tribes have fought against outside interference for centuries. They were never fully under the control of British authorities during colonial rule or Pakistani authorities since independence in 1947.

"I hope that they proceed cautiously and not accept an outcome that would give extremist elements the right, or the ability, to use the FATA area with impunity to carry out attacks on Pakistan and carry out attacks on Afghanistan or the United States or the rest of the world," Negroponte said.

"There is a lot at stake here and we have made that point repeatedly," he said, saying some Pakistanis believe it is worth trying negotiations "before one has to resort to more vigorous security measures."

"I think the response to that is that approach was tried before ... and it turned out not to work," he added.

Reuters