By Jon Leyne BBC correspondent in Washington

The American Secretary of State, Colin Powell, is beginning a new mission to calm tensions between India and Pakistan.

He arrives in Delhi on Saturday and later moves on to Pakistan, before visiting six countries in south-east Asia.

Both India and Pakistan feel they have made more than enough concessions to the United States

Mr Powell is still the "rock star" of the Bush administration - the one with unrivalled charisma and enduring popularity, both at home and abroad.

But that is proving no guarantee of success - either in Washington or abroad.

The immediate threat of war between India and Pakistan may have receded, but the situation between the two countries is still very tense.

Colin Powell will be attempting to stabilise relations for the longer term.

Dialogue

He will be looking for the reopening of direct talks between India and Pakistan.

"I will see if there are any other actions that can be taken that will reduce the level of violence or the potential for violence," Mr Powell told reporters before leaving Washington.

Kashmir - Powell hopes for a dialogue over the disputed region

"I'm sure we will have discussions on the possibility of a dialogue at some point in the future between the two sides that will deal with the question of Kashmir."

But on this, his third visit in less than a year, the secretary of state could receive quite a frosty reception.

As yet, no meeting with the Indian prime minister has been scheduled - there is even some doubt over whether Mr Powell will see the Pakistani President, Pervez Musharraf.

Hardening attitudes

Both India and Pakistan feel they have made more than enough concessions to the United States.

Powell tour

India Pakistan Thailand Malaysia Singapore Brunei Indonesia Philippines

The prospect of elections in both countries in the next few months is also hardening attitudes.

"Musharraf cannot be seen to give any more. He's not in a position to go any further because it will be difficult for him politically," explained Aqil Shah, an analyst with the International Crisis Group.

By contrast the Indian foreign ministry spokeswoman, Nirupama Rao, warned that Delhi would convey its concern over what it believes is continuing infiltration by militants across the Line of Control - the ceasefire line that separates Indian- and Pakistani-controlled Kashmir.

Powell's future

Mr Powell may be on surer ground when he goes on to south-east Asia - where there are important issues to discuss on the war on terror.

The secretary of state will be looking for more co-operation on freezing the financial assets of those suspected of terrorism.

For some reason the press feels it is necessary every two weeks to write a story about whether I am up or whether I am down

Colin Powell

He will also be looking at possible further military co-operation with the Philippine and Indonesian Governments.

This trip comes at a time when questions are asked, almost daily, about Mr Powell's own future within the Bush administration.

President Bush's decision to stop funding the UN population fund is just the latest of a series of policy reverses suffered by Mr Powell.

He is known to be a reluctant supporter of the policy of isolating Yasser Arafat. And from the first days of the administration he has advocated a dialogue with the North Koreans which has still not got off the ground.

Bad patch

Ironically, Mr Powell is one of the most popular secretaries of state within his own department for perhaps two decades.

Staff at "State" are enjoying having a boss who seems genuinely to care for their welfare - even while their department's influence dwindles within the administration.

Mr Powell himself answer those questions about his future with a weary denial: "Now for all those resignation stories, I don't know," he told one group of reporters earlier this week.

"I can go back and do a Lexis-Nexis [a computer search] and you've been doing them every two weeks since I came in here last year, but I'm sure you'll continue to do them. It's great reading."

To another group of reporters he said: "For some reason the press feels it is necessary every two weeks to write a story about whether I am up or whether I am down, whether I am in or whether I am out, and whether I am going to resign or whether I'm going to stay forever."

"But I have no intentions to resign, no plans to resign."

Those who know him say Mr Powell is not the sort of person who would even consider resigning.

But within the internal policy battles inside the Bush administration he certainly seems to be going through a bad patch.