WASHINGTON (AP) _ President Bush said Friday the United States is ''not looking for any fight'' with Baghdad but will keep military forces in Iraq as long as it takes to help Kurdish refugees.

''I don't think Saddam Hussein is dumb enough to want to have (to) run into the U.S. troops again,'' Bush said.

He also expressed confidence Saddam will be deposed eventually. ''His people don't like him and it's only terror that's keeping him in power,'' Bush said, adding that there will not be normal relations between Baghdad and Washington as long as Saddam is in control.

The president made his comments at an impromptu news conference on the White House South Lawn during a tree-planting ceremony marking Arbor Day. He helped plant a purple leaf beech.

On other topics:

- Bush said Secretary of State James A. Baker III had made progress in trying to arrange a Middle East peace conference. ''It's fair to say that, though problems remain, I think the bottom line is there's some reason for optimism,'' he said.

The president said he would not disclose any details of Baker's talks, which produced a pledge from Moscow to cosponsor a peace conference. ''There are still some sticky problems, but we're not going to give up. We're going to continue to try to bring peace to that troubled corner of the world.''

Baker abruptly flew home from Israel on Friday after learning of the death of his mother.

- The president said no date has been set for a summit with Soviet President Mikhail S. Gorbachev. He said there was only ''modest progress'' in arms control negotiations during Baker's meeting in the Soviet Union with Foreign Minister Alexander Bessmertnykh.

- Bush broadly hinted he will cut back on the policy authorizing White House chief of staff John Sununu to use military planes for all his political and personal travel.

''There might well be changes in it because I want this administration to continue to be above the perception of impropriety,'' Bush said. ''So if that requires changes, fine.''

Speaking about developments in Iraq, Bush said he was confident that Baghdad would continue to keep military forces away from the refugee camps in northern Iraq.

''They don't want to tangle with the U.S. again,'' he said. ''They learned that the hard way and the forces are there to be sure'' Iraq keeps its own troops away. ''We're not looking for any fight. We want to help these Kurds ... and I might say at considerable cost. We're doing it because it's right.''

On Capitol Hill, Gen. Colin Powell said the United States was beefing up its forces in Iraq and that the Kurds should feel more secure about coming down from the mountains. Moreover, he said international relief efforts were increasing.

''So I think we're in pretty good shape, better than we were a couple of days ago,'' said Powell, the chairman of the Joint Chiefs of Staff.

Asked how long U.S. troops will remain in Iraq, he said, ''I had no time line in mind when we sent them in there. They'll stay as long as needed.''

About 7,000 U.S. troops are positioned in northern Iraq and in nearby Turkey to assist hundreds of thousands of refugees who fled their homes after a failed uprising against Saddam.

U.S. military officials said 90 more troops entered the Zakho area Friday and that 300 or more were en route to bolster the U.S. military presence.

''I do not want to intervene and get our troops hauled into some conflict that's been going on for years,'' Bush said. ''But when it comes to helping people, the United States is today doing what it's always done: being out in front on the relief effort.''

He said he did not know how long U.S. troops would be in Iraq. ''They're going to stay there as long as it takes to be sure these refugees are taken care of, and not a minute longer.''

In New York, U.N. Secretary-General Javier Perez de Cuellar said the camp at Zakho will be turned over to U.N. control within days. A U.S. diplomat said the complete transfer of authority would probably take weeks.

Bush said he was committed to bringing U.S. troops home but that ''we will do what's necessary to see that this refugee aid gets to the people that need it and gets there so that they can have it in safety.''

He expressed skepticism about chances to end Iraq's own turmoil. ''I don't know that there's going to be lasting peace in Iraq,'' the president said. ''Peace has escaped those people for years.''

He said he hoped a tentative agreement between Saddam and Kurds would ease tensions but added, ''I can't certify that'' it will.