EU foreign policy chief Javier Solana and Iran's top nuclear negotiator Saeed Jalili are to meet in Geneva on Saturday.

"I'm hoping a lot will come from the meeting, but I have no concrete expectations," said Kouchner, whose country is the current holder of the EU's rotating presidency.

"It's too early to say whether there will be any progress," he told reporters.

US Under Secretary of State William Burns will also sit in on Saturday's meeting -- marking the first time that Washington, which broke off relations with Tehran in 1980 -- has participated in the negotiations aimed at convincing Tehran to suspend uranium enrichment.

"The presence of an American is good news," Kouchner said at a joint news conference held with his Austrian counterpart, Ursula Plassnik.

He had already been informed on Wednesday by US Secretary of State Condoleezza Rice that a US official would be present at the talks, Kouchner said.

"France has always said that not only sanctions need to be imposed, dialogue is necessary as well," he said.

Kouchner noted that the three sets of UN Security Council sanctions had not managed to persuade Tehran to suspend uranium enrichment, which the West fears could be used to make the fissile material of nuclear bombs.

France and French oil giants had frozen their investment in Iran and Kouchner said he hoped all countries would do the same.

For her part, Austrian Foreign Minister Plassnik said she also welcomed the US presence at the talks.

"I welcome the fact that the US will be present and listening. It's a welcome meeting," Plassnik said.

"I wouldn't say negotiations. I prefer to say talks."