The United States said on Sunday that the international war against terrorism cannot be won unless Pakistan stops sending terrorists into Jammu and Kashmir.

"Working with dozens of like-minded nations, the United States and India will win the war on terrorism. That war will not be won unless terrorism against India is ended once and for all," US Ambassador to India Robert Blackwill said at the 50th anniversary celebration of the Indian Institute of Technology.

Washington supports dialogue between New Delhi and Islamabad, but first there has to be an end to cross-border terrorism, he said, adding that the Kashmir issue, which is the key to flowering Indo-Pak relations, must be addressed peacefully.

"But that can only be done in a situation in which the terrible acts of terrorist violence that characterise Jammu and Kashmir stop," the ambassador said in his keynote address.

"The Line of Control cannot be changed by violence. On the contrary, in the absence of a jointly agreed Indo-Pakistani alternative, everyone should ensure that there is continued sanctity of the Line of Control," he said.

He said the US believes that Indo-Pak differences must be solved bilaterally.

"We are not going to mediate. We would welcome diplomatic interactions between India and Pakistan, but first there has to be an end to terrorism emanating from Pakistan against India," Blackwill said.

The US will continue to urge Pakistan President Pervez Musharraf to do everything in his power to end infiltration into Jammu and Kashmir, he said.

The envoy said some people are of the view that when identifying terrorists, there is a need to consider history, circumstances and other subtleties.

"To the contrary I say that defeating terrorism for the United States and India is not subtle. It is a matter of survival for ourselves, for our democratic values, for our religious freedom, for our children, for everything we hold dear," Blackwill said.

"Let us please name those for what they are who murder innocent for political motives and who seek to bring down the very pillars of democracy -- in New York, in Washington, at the assembly in Srinagar, at the Parliament in New Delhi.

"These murderers are not misunderstood ideals, they are not disadvantaged dissidents, they are not religious perfectionists and they, most assuredly, are not freedom fighters. They are terrorists and we should be careful always to call them exactly that," the ambassador said.

Terrorism in J&K: The Complete Coverage