Washington  - US President George W Bush said Tuesday the United States has made it clear to Pakistan that it will do "what is necessary" to protect American soldiers.

The region along Pakistan's border with Afghanistan that Taliban and al-Qaeda use to plot terrorist attacks and assault US and NATO forces in Afghanistan is "one of the most important challenges we will face" in fighting terrorism.

"The problem is most pronounced in Pakistan, where areas along the Afghanistan border are home to Taliban and to al-Qaeda fighters," Bush said.

The US pledged to support the Pakistani government's efforts to go after the militants, but Washington and Islamabad have clashed over strikes inside Pakistan by US unmanned aerial vehicles.

"We have made it clear to Pakistan and to all our partners that we will do what is necessary to protect American troops and the American people," Bush said.

In recent months, the US has stepped up airstrikes inside Pakistan's mountainous, ungovernable tribal region to increase pressure on the Taliban and al-Qaeda and in response to a dramatic rise in attacks inside Afghanistan.

India also blames Pakistan for the November 26 terrorist attacks in Mumbai that killed more than 170 people. (dpa)