Days before a key meeting on Iran's disputed nuclear program, U.S. Secretary of State Hillary Rodham Clinton called on Tehran Friday to begin proving its peaceful intentions and warned that a nuclear-armed Iran would lead to a regional arms race.

Asked what she expected from Monday's meeting in Geneva between Iran and officials from six countries trying to contain Iran's nuclear program, Clinton said: "That's in the hands of the Iranians."

Stressing that Iran is legally entitled to the peaceful use of nuclear energy under international safeguards, she expressed hope that the Geneva talks would lead to a breakthrough.

In an interview Friday with the BBC, Clinton gave an unusually clear signal that the Obama administration accepts that Iran could eventually be permitted to enrich uranium on its own — a practice now opposed by the West because of suspicions that Iran will secretly use the material to build a bomb.

"We've told them that they are entitled to the peaceful use of civil nuclear energy, but they haven't yet restored the confidence of the international community to the extent where the international community would feel comfortable allowing them to enrich," Clinton told the BBC. "They can enrich uranium at some future date once they have demonstrated that they can do so in a responsible manner in accordance with international obligations."

In her speech at an international security conference earlier in the day, Clinton said the Obama administration remains open to the possibility of direct U.S.-Iranian talks on the nuclear issue — an approach the Iranians have repeatedly rejected.

"We continue to make this offer of engagement with respect for your sovereignty and with regard for your interests — but also with an ironclad commitment to defending global security and the world's interests in a peaceful and prosperous Gulf region," she said.

There has been more than a year of impasse that produced tighter U.N., American, Asian and European sanctions on Tehran and some stinging blows — including international oil companies leaving Iran and Russia's refusal to deliver a long-awaited anti-aircraft system to Iran's military.

"There is a level of concern that must be addressed by Iran," she said in a question-and-answer session after delivering the keynote speech at the conference. "Otherwise we are left drawing the worst of conclusions" about Iran's intentions. "And that is a recipe for the further destabilizing of this region in ways that would have long-term consequences."

She urged Iran to come to Geneva prepared to "firmly, conclusively reject the pursuit of nuclear weapons."

Iran insists its nuclear program is for peaceful purposes only, but it has begun taking steps toward enriching uranium at a level sufficient to make bombs.

If Iran believes that acquiring nuclear weapons would improve its security and strengthen its standing in the Middle East and the world, "that is an absolutely wrong calculation because it will trigger an arms race that would make the region less stable, less uncertain and cause serious repercussions far beyond the Gulf," Clinton said.

She pointedly said her remarks were directed at the Iranians in her audience, including Foreign Minister Manouchehr Mottaki. The Iranian minister is scheduled to address the same conference on Saturday.

Aboard her plane later, Clinton said that as she walked by Mottaki after finishing her speech in a hotel ballroom she spotted him shaking hands in the crowd.

"He saw me and he stopped and began to turn away and I said, 'Hello, minister.' He just turned away." she said.

Earlier Friday, Sheik Khalid bin Ahmed Al Khalifa, Bahrain's top diplomat declared that the Middle East "can never live with" a nuclear-armed Iran — remarks that echoed some of the bluntly private comments about Iran from Persian Gulf leaders that were divulged in recently released WikiLeaks diplomatic documents.

The Bahraini foreign minister was unequivocal in his insistence that Iran must not move toward a nuclear bomb-making capability. He said no one questions Iran's right to develop nuclear energy for peaceful purposes.

"When it comes to taking that power to developing into a cycle for weapon-grade (nuclear material), that is something that we can never accept and we can never live with in this region," he said. "We've said it to Iran and we've heard it from all."

He was responding to a reporter's question about a WikiLeaks disclosure of a secret State Department cable quoting Bahrain's King Hamad bin Isa Al Khalifa as saying privately that Iran must be stopped from getting the bomb.

Until now, Arab worries generally have been expressed publicly in careful, diplomatic language with the emphasis on dialogue and diplomacy.

The WikiLeaks disclosures showed private concerns about Iran expressed by a range of Arab leaders.

One message said Bahrain's King Hamad "argued forcefully for taking action to terminate their (Iran's) nuclear program, by whatever means necessary. That program must be stopped. The danger of letting it go on is greater than the danger of stopping it."