Iran blamed world powers on Saturday for delays in long-stalled talks over its controversial nuclear programme, after Western diplomats said Iranian uncertainty over the venue had delayed the negotiations.

State broadcaster IRIB said deputy EU foreign policy chief Helga Schmid had asked Iranian deputy nuclear negotiator Ali Bagheri on Friday to move the talks from January to February.

World powers "are not ready to hold the negotiation in January," IRIB quoted Schmid at telling Bagheri by telephone. "She suggested a new date in February."

But "Bagheri stressed that Iran is ready to hold the talks, asking the other party to remain committed to the date agreed for talks in January," it added.

Schmid's boss, Catherine Ashton, represents the so-called P5+1 group of the United States, China, Russia, Britain, France plus Germany in talks on Iran's nuclear ambitions.

The West suspects Iran of attempting to develop a bomb, but Tehran strongly denies that, insisting nuclear its activities are purely peaceful.

On Friday, European diplomats voiced disappointment that "there was still no meeting," and Ashton spokeswoman Maja Kocijancic said contacts on when and where the talks will be held "are still taking place."

The last round of negotiations in Moscow in June ended without breakthrough. Tehran rejected P5+1 calls for it to scale back its nuclear programme and asked for relief from sanctions that began to bite in 2012.

The talks are focused on Iran's current activities, in particular its capacity to enrich uranium to fissile purities of 20 percent. The process can be used for peaceful purposes but also for creating the core of a nuclear bomb.

Iran says it has no intention of giving up what it calls its nuclear "right."

Ali Akbar Velayati, a top adviser to Iran's supreme leader, was quoted by Mehr news agency on Saturday as saying "the right of using nuclear energy for peaceful purposes is a right that Iran will not give up, and everyone (in Iran) agrees on it."

"The nuclear issue is a strategic issue for Iran," he said.

In Washington on Thursday, Senator John Kerry, the secretary of state designate, said the United States would remain committed to its dual-track policy towards Iran with focus on talks and tough global sanctions.

"If their programme is peaceful, they can prove it, and that's what we're seeking," Kerry said, adding that the US will not be satisfied with containing Iran but will seek to stop it from obtaining a nuclear weapon.

Israel, the Middle East's sole if undeclared nuclear weapons state, has refused to rule out taking military action against Iran to prevent it from also acquiring the bomb.