Deputy Secretary of State Richard Armitage leaves Washington Tuesday for South Asia as part of a stepped-up U.S. diplomatic effort to defuse the military confrontation between India and Pakistan. Mr. Armitage will be followed to the region almost immediately by Defense Secretary Donald Rumseld.

Mr. Armitage, a blunt-speaking former top Pentagon official, is due in Islamabad Thursday and goes to New Delhi Friday with specific ideas on how to bring the two nuclear-armed rivals back from the brink of full-scale war.

At a briefing here, State Department spokesman Philip Reeker said the first step in ratcheting-down the crisis should be action by Pakistan fulfilling its stated commitment to end the infiltration of militants across the "line of control" in Kashmir:

"What we want to see is that action, because we think that's very important. And then some reciprocity on the side of the Indians so that the Pakistanis can visibly see that there is goodwill on both sides," he said. "And then we can look at possible confidence-building measures that both sides can take to continue a de-escalation and create an environment that is more conducive to the dialogue that we think is necessary to solve these problems."

In preparation for his mission, Mr. Armitage spoke by telephone Monday with British Foreign Secretary Jack Straw, who completed his own trouble-shooting mission to the region last week.

In a pre-trip television interview, the deputy secretary also said he expects a briefing from Russian officials on the discussions President Vladimir Putin is having with Indian Prime Minister Atal Bihari Vajpayee and Pakistani President Pervez Musharraf at the Central Asian regional summit underway in Kazahkstan.

Mr. Armitage welcomed a weekend comment by President Musharraf that "no sane individual" could think about starting a nuclear war. But Mr. Armitage also said that when large-scale hostilities erupt between such well-armed parties "reason and logic," as he put it, "seem to go out the window."

He said India has a right to be aggrieved over acts of terror by Muslim extremists, yet as an emerging superpower, he said he hopes India can restrain itself and act responsibly.

Mr. Armitage will be followed to the region next weekend by Defense Secretary Rumsfeld, who added India and Pakistan to a Middle East trip as part of what Secretary of State Colin Powell described Monday as a "full-court diplomatic press" to ease the South Asia crisis.