Britain said Saturday it hopes to lower the number of troops it has in Iraq, as former President Clinton warned that the United States and its supporters should not leave Iraq prematurely.

At the fourth and final day of the World Economic Forum, Iraqi officials urged more time and patience as they struggle to rebuild their country.

British Foreign Secretary Jack Straw said London was looking to withdraw some of its 8,500 troops later this year, but did not provide a timetable.

"We hope to do some of that during the course of this year in at least two of the provinces, not Basra. I can't give a date and I can't give numbers, but that's our intention," Straw said at the forum in the Swiss mountain resort of Davos.

Former President Clinton said the United States and its supporters should not leave Iraq too quickly.

"We shouldn't just precipitously give this thing up and say it can't work," Clinton said. "If this thing works, it'll be a good thing for everybody in the Middle East. If it doesn't, it'll be trouble."

Straw took aim at Iraq's neighbor, saying British officials will hold talks Monday with a senior Iranian nuclear negotiator before a decision at the International Atomic Energy Agency in Vienna, Austria, on Feb. 2 on whether to refer Iran to the U.N. Security Council over its nuclear efforts.

"The problem is one of Iran's own making," Straw said. "What we have said is they have to provide objective guarantees that their nuclear capability is solely for civil nuclear power purposes."

Iran provoked an international outcry on Jan. 10 when it ended a two-year freeze and resumed small-scale enrichment of uranium — a process that can be used to produce fuel for generating electricity or material for atomic bombs.

To resume enrichment, Iran had to break the seals of the International Atomic Energy Agency, the nuclear monitoring body. Iran argues its program is intended only to generate electricity. The United States argues it is a ruse to develop nuclear weapons.

In Tehran, Gen. Yahya Rahim Safavi, the chief of Iran's Revolutionary Guards, warned the U.S. and Britain that it would respond with missiles if attacked, a clear threat to Israel.

Meeting on the sidelines of the forum, 20 ministers from the World Trade Organization reaffirmed a timetable to conclude the Doha round of trade liberalization by the end of 2006. The Doha round — launched in Qatar's capital in 2001 aiming to slash tariffs and subsidies — is well behind schedule, despite a limited agreement at a ministerial meeting last month in Hong Kong.

"There's still a lot of work to be done," said Mark Vaile, Australia's deputy prime minister and trade minister.

Vaile said to move the talks forward the European Union must make further cuts to its farm import tariffs and Brazil and India must offer easier access for industrial goods and services. The United States also needs to offer more cuts in payments to its farmers, he added.

"It's all of those things together," Vaile said.

As the world's leaders met inside, about 100 demonstrators marched peacefully past the Congress Center, chanting "Wipe out WEF," in reference to the World Economic Forum, and "Klaus, come out," referring to Klaus Schwab, founder and head of the Forum.

Another group of protesters was dressed in corporate attire, bearing briefcases and cans of beer and poking satirical fun at the CEOs at the forum.

"It's high theater," Tomas Niederberger of Zurich said of the annual meeting. "We're making a point about it being absurd."

Inside, Hajim al-Hassani, president of the Iraqi National Assembly, said that U.S. troops would not leave until the government could ensure its own security.

"There is a formula that has been agreed upon that withdrawal of the troops from Iraq should be a function of building Iraqi security," he said.