Washington: Iran's growing and lethal interference in Iraq and elsewhere in the region is a source of increasing concern, the top US military leader said today, suggesting Tehran was on a collision course with the US.

Admiral Michael Mullen, the chairman of the Joint Chiefs of Staff, said the United States would continue to confront Iraq militarily inside Iraq and exert diplomatic and economic pressure to influence its behaviour.

But in a news conference here, Mullen said Iran had not responded to such pressure in the past and instead appears to have steadily increased its support for militant groups in Iraq and elsewhere over the past two years.

"I have no expectations that we are going to get into a conflict with Iran in the immediate future," he said.

"But I am concerned over time that in these last couple of years these tensions continue to rise, Iran does not respond and in fact seems to be ratcheting it up in terms of their support for terrorism.

"And I am concerned about where that goes in the long term. And I don't have a time and I don't have a solution with respect to that. I think we need to continue to press using all available means," he said.

Mullen's comments carry particular weight because he is seen as a moderate who has voiced concerns about the impact of the war in Iraq on US military forces.

He said today that a third conflict in the Middle East would be "extremely stressing on us," but added that it would be "a mistake to think we re out of combat power."

His comments came a day after the United States made public charges that Syria was secretly building a nuclear reactor with North Korean help until it was destroyed by an Israeli air strike in September.

Source : PTI