According to national security adviser John Bolton, the US rejected a proposal to hold off on the re-imposition of sanctions against Iran in return for a “rollback” of Iranian forces from Syria.
Bolton was vague on this offer, beyond suggesting it came from Russia. He wasn’t clear if “holding off” on the sanctions meant a delay or a cancellation, and didn’t say if the “rollback” of Iranian troops meant them leaving Syria outright, or simply being restricted to certain areas.
Either way, the US rejected the proposals, and doesn’t appear willing to trade the sanctions for Iranian military concessions. Bolton still said the US is determined to force all Iranian forces across the planet to return to Iran, and that he believes Russia agrees with that goal.
How the US intends to achieve that is another matter, and one Russia clearly does not agree with. Russia has not backed the US sanctions, and has said they can’t force Iran out of Syria so long as Syria wants them to stay. That presumably extends to expelling Iran from everywhere else, though in practice Iran doesn’t have a lot of military deployments abroad.