VIENNA — World powers are proposing to Iran to hold their first round of talks in six months on Tehran’s nuclear programme already in the first half of December in Istanbul, diplomatic sources say.

“The United States want to move fast,” one senior diplomat said after talks in Brussels last Wednesday among negotiators from the “P5+1” — the United States, Russia, China, Britain, France and Germany.

“We aim to propose [to Iran] to sit around the table in the first two weeks of December... possibly in Istanbul if the Iranians accept this,” he said.

A second envoy from one of the six countries involved also said this was the case.

If this proves too ambitious, then the group will push for the talks to take place in January, the diplomats said. “This fits with our aspirations,” said a third.

Following the Brussels meeting, the first since US President Barack Obama was re-elected on November 6, EU foreign policy chief and P5+1 head negotiator Catherine Ashton said that the group wanted talks with Iran “as soon as possible.”

US State Department spokeswoman Victoria Nuland said Washington was awaiting the outcome of a mooted upcoming “contact” between Ashton and Iran’s negotiator Saeed Jalili.

In Iran, which has not so far reacted publicly to Ashton’s statement from last week, Foreign Minister Ali Akbar Salehi, as quoted by the official IRNA news agency, also refused to be drawn on the date or location of a next meeting.

The Turkish city of Istanbul was where in April the P5+1 and Iran held their first talks in 15 months, seen at the time as a renewed push by Obama to ease tensions after his initial efforts early in his first term in 2009 floundered.

At the subsequent round in May in Baghdad, the P5+1 set out a list of proposals that included Iran halting its most sensitive nuclear activities, but Tehran rejected them at the next get-together in June in Moscow.

It says its nuclear drive is peaceful but many in the international community suspect its real aim is to develop atomic weapons.

The UN Security Council has imposed four rounds of sanctions on Iran which have been augmented this year by painful Western restrictions on its vital oil exports, hitting the economy hard.

With Iran feeling the pinch from sanctions and Obama now freed from the constraints of a lengthy election campaign, conditions would appear favourable to make progress.

However, it is far from clear whether the P5+1 are ready to consider easing sanctions, a key demand from Iran.

Another diplomat said Wednesday that the six powers have not yet even agreed among themselves what to put on the table, saying there was a “range of perspectives” being considered.

Signals coming out of the Islamic republic, which has used the six months since Moscow to continue expanding its nuclear programme, give little reason to expect a new spirit of compromise.