Iranian officials travelled to Doha for talks with Qatar on a possible final agreement with Washington, amid growing signs of a breakthrough in US-Iran talks.
Iran said talks with the US are focused on ending the war rather than the nuclear file, insisting no imminent agreement with Washington can yet be claimed.
As diplomatic efforts continue between Tehran and Washington, Iran warned that any renewed military confrontation could escalate into a far broader conflict.
Iranian analysts say Washington has softened parts of its negotiating position as US officials warn Tehran used the ceasefire to strengthen its military power.