World powers urged Iran on Friday to rapidly accept a European Union invitation to resume talks aimed at resolving the standoff over Tehran's controversial nuclear programme.

Top diplomats from the United States, China, Russia, France, Germany and Britain met in Brussels with EU foreign affairs chief Catherine Ashton to discuss the implementation of new UN sanctions against Iran, the group said in a statement.

"We confirmed our readiness to continue dialogue and interaction with Iran," said the political directors from the foreign ministries of the six nations.

They added that they "looked forward to an early reply from the Iranian nuclear negotiator Jalili to Catherine Ashton's letter proposing the rapid resumption of talks on the nuclear issue."

Ashton said last month that she had written a letter to Iran's chief nuclear negotiator, Saeed Jalili, inviting him to resume negotiations on behalf of the five UN Security Council permanent members -- the United States, Russia, China, Britain, France -- plus Germany.

But the Iranians have yet to respond to her invitation.

A senior EU official said the six world powers are expecting a response, or even a meeting, in mid-August at the earliest or in September.

The location of such a meeting would also need to be decided, but the official said it was unlikely to take place in Tehran at this stage.

"It would be too soon to be talking in Tehran, it would give too high expectations," the official said.

The UN Security Council imposed a fourth set of sanctions against Iran in June to punish Tehran for refusing to halt its uranium enrichment work, the most sensitive part of its atomic drive.

Since then, the United States and the EU have imposed their own sanctions targeting the Islamic republic's key energy sector.

The United States, European Union powers and Israel suspect Iran is hiding a secret nuclear weapons programme, but Tehran denies the charge, insisting that it is a peaceful drive to provide civilian energy.