Munich: Iran’s foreign minister welcomed the United States’ willingness to hold direct talks with Tehran in the standoff over its nuclear programme but did not commit to accepting the offer.

US Vice President Joe Biden told a security conference Saturday the US is prepared to talk directly with Iran but insisted Tehran must show it is serious.

Iran’s Ali Akbar Salehi told the same conference Sunday that Iran views recent US statements “with positive consideration”.

But he was wary about prospects for talks. He says Iran must be sure the US has “a fair and real intention to resolve the issue” and complains about “threatening rhetoric”.

New talks involving all five permanent members of the UN Security Council plus Germany are due soon. Salehi said they’d be held February 25 in Kazakhstan.

Washington has indicated in the past that it’s prepared to talk directly with Iran, and talks involving all five permanent members of the UN Security Council plus Germany have made little headway. Several rounds of international sanctions have cut into Iran’s oil sales and financial transactions.

Last month Iran, in a defiant move ahead of a new round of talks expected soon with the six powers, announced plans to vastly increase its pace of uranium enrichment. That can be used to make both reactor fuel and the fissile core of warheads.

Biden told an international security conference that “there is still time, there is still space for diplomacy backed by pressure to succeed”. He did not specify any timeframe.

Russian Foreign Minister Sergey Lavrov, whose country is a key player in the six-nation talks with Iran, said he “would strongly support what Vice President Biden said about the need for incentives to be clearly shown to Iran”.

“We have to convince Iran that it is not about the regime change,” he said.