Major powers on Tuesday offered Iran limited sanctions relief in return for a halt to the most controversial part of its nuclear program, and Iran promised to respond with a proposal on the same scale.

The talks in Kazakhstan were the first in eight months between Iran and the five permanent members of the U.N. Security Council plus Germany - the "P5+1" - on a decade-old dispute that threatens to trigger another war in the Middle East.

Iran has used the time since the last meeting in June to further expand activity that the West suspects is aimed at enabling it to build a nuclear bomb, something that Israel has suggested it will prevent by force if diplomacy fails.