Washington: More Afghan security forces would have to be deployed on Af-Pak border if the issue of safe havens in Pakistan is not resolved, a top US Commander has said.

"Chances are very good that, if the issues in the Pakistani safe havens do not resolve in our favour one way or the other, we'll probably have to have a larger presence of the ANSF than we had anticipated, which may require us to thin the ANSF in other places in Afghanistan," General John Allen, Commander of US and NATO forces in Afghanistan told US lawmakers at a Congressional hearing on tuesday.

Responding to questions from US Congressmen, General Allen said the presence of safe havens in Pakistan continues to be a threat to the war against terrorism campaign.

"As you know, the nature of the Taliban in those safe havens differs, varies according to where they are geographically.

"I believe that, in the south, the southern Taliban elements out of the Quetta Shura Taliban -- their momentum has been successfully thwarted both by ISAF forces and the forces of the ANSF," he said.

"It is in the east where I spend a great deal of my time focusing on the Haqqani Network and on the Tehrik-e Taliban Pakistan and other of the Taliban elements, the Commander Nazir Group in Paktika, the Haqqani Network in North Waziristan," he added.

"If we don't see some political outcome from reconciliation, which can have effect on safe havens; if we don't see Pakistani action to address the safe havens, then ultimately we're going to have to thicken the defences of the Afghan people to provide as much friction as possible to protect the strategic centre of gravity, which is Kabul and the security zone around Kabul," Allen said.

"We'll be watching the campaign unfold this year and next year to determine ultimately, in consultation with our Afghan partners, how they will dispose their forces in the end," he said.

In his testimony, James Miller, Commander, NATO International Assistance Security Assistance Force (ISAF), said success in Afghanistan will depend on the support of its neighbours, particularly Pakistan.

"Like Afghanistan's other neighbours, Pakistan has legitimate interests that should be understood and must be addressed. Pakistan also has responsibilities. Most importantly, it needs to take further steps to ensure that military and extremist groups cannot continue to find safe haven in Pakistani territory, Miller said.

"Pakistan has powerful incentives to do so. In 2011 alone, some 2,000 attacks in Pakistan resulted in about 2,400 deaths, mostly from improvised explosive devices," he said.

(Agencies)