Tehran: Iran on Wednesday said it has formally agreed to resume the controversial nuclear programme talks with six major powers. The talks were stalled since January.

Iran's official confirmation came in a letter delivered to the European Union foreign policy chief Catherine Ashton who spearheads the talks on behalf of the so-called P5+1 powers.

"We welcome your return to the negotiations based on cooperation on the common points," Iran's top nuclear negotiator Saeed Jalili was quoted as saying in the letter. It said the letter was handed over by Tehran's envoy to the EU.

In Brussels, Ashton's office confirmed receiving Jalili's response to a letter sent by Ashton in early February.

Jalili said in his letter that ‘the developments in recent months have shown that Iran's proposal package three years ago was based on the correct understanding of the realities.’

He added that respecting the nation's rights and refraining from pressure are the two main pillars of cooperation.

Ashton's letter, which followed unsuccessful January talks in Istanbul, reiterated the group's position on Iran's contentious nuclear issue.

Prior to Istanbul talks, Iran had participated in similar negotiations with the world powers in December 2010 in Geneva.

According to Ashton's spokesman, she also affirmed that the world powers were keen to continue talks with Iran without any preconditions.

Iran maintains that negotiations must revolve around its package given to world powers three years ago which does not specifically speak about its own atomic programme but insists rather on discussion about global nuclear disarmament and world security.

At the close of the Istanbul talks, Ashton said ‘it remains essential that Iran demonstrates that its nuclear programme is peaceful.’

"We had hoped to embark on a discussion of practical ways forward, and have made every effort to make that happen. I am disappointed to say that this has not been possible," she said at that time.

On Monday, Iranian President Mahmoud Ahmadinejad had said in Istanbul that Tehran would respond "soon" to Ashton's letter.