Iran said it was prepared to make an offer to major powers in talks on its nuclear program in Kazakhstan on Tuesday, February 26 after the United States proposed limited sanctions relief in return for a halt to the most controversial work, Reuters reported.

The first meeting in eight months between Iran and the five permanent members of the UN Security Council plus Germany - the "P5+1" - aims to resolve a dispute that threatens to trigger another war in the Middle East.

The negotiations in the city of Almaty - which follow inconclusive meetings last year in Istanbul, Baghdad and Moscow - were expected to run through Tuesday and Wednesday.

But with the Islamic Republic's political elite preoccupied with worsening infighting before a presidential election in June, few believe the meeting will yield a quick breakthrough.

A U.S. official said on Monday that the powers' updated offer to Iran - a modified version of one rejected by Iran last year - would take into account its recent nuclear advances, but also take "some steps in the sanctions arena".

This would address some of Iran's concerns but not meet its demand that all sanctions be lifted, the official said.

In Almaty, a source close to the Iranian negotiating team said on Tuesday that Iran would put up a counterproposal.