GENEVA - The United States and Iran, poised to meet today in Geneva in their first face-to-face talks on Iran's nuclear program, sent more signals Friday that they may be ready to step away from confrontation and begin a grueling process to resolve three decades of hostility.

Until now, the Bush administration had refused to hold direct talks with Iran, except under the precondition that Iran heed U.N. demands to suspend uranium enrichment, a process that can produce nuclear-weapons fuel. Iran, which says it's legally enriching uranium to produce fuel for power-generating reactors, on Friday welcomed the sudden U.S. reversal of policy.

"The new negotiating process [and] the participation of a U.S. diplomat look positive from the outset," Iranian Foreign Minister Manouchehr Mottaki said during a visit to Turkey. "We hope that is reflected in the talks."

Mottaki praised President Bush's decision to send Undersecretary of State William Burns, the third-most-senior U.S. diplomat, to the talks as "a new positive approach."

He said he also hoped deals could be reached on direct air links between Iran and the United States, and the opening of the first American diplomatic office in Tehran since the sides broke relations after the 1979 Islamic revolution.

Secretary of State Condoleezza Rice reiterated Friday that the Bush administration won't enter full-scale negotiations with Iran until it agrees to a full freeze of uranium enrichment.

"It should be very clear to everyone, the United States has a condition for the beginning of negotiations with Iran, and that condition remains the verifiable suspension of Iran's enrichment and reprocessing activities," Rice said in Washington.

The shift to direct talks follows months of rising tensions over the nuclear issue, fueled by Iranian missile launches, U.S. and Israeli threats to destroy what they charge is a secret Iranian nuclear-weapons program, and Iranian President Mahmoud Ahmadinejad's calls for Israel's destruction.

What's on the table

The Geneva talks between European Union foreign-policy chief Javier Solana and Saeed Jalili, Iran's chief nuclear negotiator, were called to hear the formal Iranian response to a package of economic, political and security incentives offered by the United States, Britain, France, Russia, China and Germany.

In return, Iran must suspend its uranium enrichment work -- something it has repeatedly refused to do -- and open negotiations on the future of the nuclear program it hid from international monitoring for 18 years.

New to the equation is Burns, who just took over the State Department's No. 3 post.

He played a key role in secret U.S. and British talks with Libya that persuaded Tripoli to give up its weapons of mass destruction programs and, in 2003, was the official who received a faxed offer from Iran to open wide-ranging talks with the United States, said Barbara Slavin, author of "Bitter Friends, Bosom Enemies," a book on U.S.-Iranian relations. The Bush administration rejected the offer.

To encourage Iran, the powers are offering to withhold new sanctions on the country for six weeks if it freezes the installation of centrifuges -- used to produce low-enriched and highly enriched uranium -- for the same period.