Iran's foreign minister could meet counterparts from the major powers in New York later this month to press efforts for a comprehensive nuclear agreement, his ministry said on Wednesday.

Mohammad Javad Zarif and the top diplomats from the six powers will be in New York to address the five-yearly review conference of the nuclear Non-Proliferation Treaty which opens on April 27.

"It could be possible that negotiations take place on the sidelines," foreign ministry spokeswoman Marzieh Afkham told a news conference.

The New York meeting will open just a week after negotiators from Iran and the powers launch talks on turning a framework agreement they reached on April 2 into a final deal.

Zarif has said those talks will begin on April 21 although he did not say where.

The negotiators must resolve a series of difficult technical issues, including the timetable for a lifting of international sanctions, by a June 30 deadline.

Iran demands that the sanctions be lifted immediately on the same day any deal is implemented.

But the world powers have said the sanctions will be lifted only gradually and want a mechanism to ensure they can be swiftly reimposed if Iran breaks its word.