Iran on Sunday announced fresh talks with world powers on its nuclear drive and said it was open to an offer from the US for two-way discussions if Washington's intention was "authentic".

Iranian Foreign Minister Ali Akbar Salehi said the six world powers planned to resume talks in Kazakhstan on February 25, and he insisted that Iran had never pulled back from the negotiations.

"I have good news, I've heard yesterday that 5+1 or EU3+3 will be meeting in Kazakhstan 25th of February," Salehi said during a panel discussion at the Munich Security Conference.

Iran and six world powers -- the US, China, Russia, Britain, France and Germany -- held three rounds of talks last year aimed at easing the standoff over Iran's nuclear activities, which Tehran insists are peaceful.

The six, known as the P5+1 or EU3+3, called on Iran to roll back its programme but stopped short of meeting Tehran's demands that they scale back sanctions, and the last round ended in stalemate in June in Moscow.

Since then, talks have been held up over disagreements on their location.

The European Union welcomed Salehi's announcement.

"It is good to hear that the foreign minister finally confirmed now. We hope the negotiating team will also confirm," said Michael Mann, a spokesman for the EU's top diplomat Catherine Ashton.

Salehi said Iran took comments by US officials, including Vice President Joe Biden, who said at the Munich conference on Saturday that Washington was ready to hold talks with Iran on its nuclear programme, "with positive consideration".

Washington ruptured diplomatic ties with Iran in the wake of the 1979 revolution, and relations remain hostile.

"We have no red line for negotiations, bilateral negotiations when it comes to negotiating over a particular subject," Salehi said.

"If the subject is the nuclear file, yes we are ready for negotiation but we have to make sure ... that the other side this time comes with authentic intention, with a fair and real intention to resolve the issue," he said.

He criticised as contradictory the desire for negotiations with Iran on the nuclear issue alongside "threatening rhetorics that everything is on the table" -- that is, a military option.

"If there is an honest intention on the other side, then we will take that into serious consideration," Salehi said.

Asked when direct US-Iranian negotiations would take place, Biden told the conference on Saturday: "When the Iranian leadership, Supreme Leader, is serious."

He said: "There is still time, there is still space for diplomacy, backed by pressure, to succeed. The ball is in the government of Iran's court, and it's well past time for Tehran to adopt a serious, good-faith approach to negotiations with the P5-plus-1."

However, in an interview with French newspaper Le Figaro published late Sunday, he warned that the "diplomatic window is closing."

"The Iranian government must approach the talks with seriousness and good faith," Biden said in remarks translated into French.

Outgoing Israeli Defence Minister Ehud Barak called in Munich for a "strong political will by the world" on the nuclear issue.

"I was glad to hear yesterday Vice President Biden saying loud and clear (that) containment is not an option," he told the conference.

Israeli Prime Minister Benjamin Netanyahu, speaking just before the formal start of talks to build Israel's new ruling coalition, said the most important mission facing the new government was preventing a nuclear Iran.

"It is a mission which has become more complicated because Iran has equipped itself with new centrifuges which reduce the enrichment time," he said.

"We cannot live with this process."

It was the first official reaction since it emerged that Tehran was planning to install more modern equipment at the Natanz uranium enrichment plant in central Iran, according to a UN document seen by AFP in Vienna on Thursday.

US ready for nuclear talks with Iran: Biden
Munich, Germany (AFP) Feb 02, 2013 - The US is ready to hold talks with Iran on its disputed nuclear programme but not just "for the exercise," US Vice President Joe Biden said Saturday.

"We would be prepared to meet bilaterally with the Iranian leadership... that offer stands but it must be real and tangible," he told the Munich Security Conference.

"There has to be an agenda that they are prepared to speak to. We're not just prepared to do it for the exercise," he added, speaking on the second day of the annual three-day gathering in southern Germany.

Kicking off his three-nation European tour that will also take in Paris and London, Biden warned Iran in a German newspaper interview Friday that opportunities for diplomacy were not unlimited but offered direct talks between Washington and Tehran.

"There is still time, there is still space for diplomacy, backed by pressure, to succeed," Biden told participants in Munich.

"The ball is in the government of Iran's court and it's well past time for Tehran to adopt a serious good faith approach to negotiations," he added.

Iran and six world powers -- the US, China, Russia, Britain, France and Germany -- held three rounds of talks last year aimed at easing the standoff over Iran's nuclear activities.

The six, known as the P5+1, called on Iran to scale back its programme but stopped short of meeting Tehran's demands to reduce sanctions. The last round ended in stalemate in June in Moscow.

Russian Foreign Minister Sergei Lavrov said here that "mistrust" must be overcome and that Iran needed to be convinced it was "not about regime change."