Iran’s U.N. mission said it would be willing to discuss its nuclear program if talks were restricted to military concerns, after its supreme leader appeared to reject President Trump’s offer to start discussions.

President Trump said a potential nuclear deal with Iran is “down to the final strokes” and could be announced within days.

Iran’s Supreme Leader Ayatollah Ali Khamenei has said calls for negotiations by “bully states” are aimed at dominating others, not resolving issues, after US President Donald Trump urged him to reach a nuclear deal.

President Trump said he sent a letter on Wednesday to Iran's supreme leader Ali Khamenei and stressed that he wants to reach a deal on the country's nuclear program. Why it matters: Trump's letter to Khamenei,

China said it would host nuclear talks with Iran and Russia, days after US President Donald Trump urged Tehran to negotiate a new deal over its atomic work or face military action.

Iran says it would consider negotiations with the United States if talks were confined to concerns about the militarization of the country’s nuclear program.

Trump previously said he wasn’t interested in talking to the ayatollahs and trashed former President Obama for the deal that slowed Tehran’s nuke progress.

The letter appears to be President Trump’s opening bid to see if a newly vulnerable Iran is willing to negotiate.

Iran’s Supreme Leader, Ayatollah Ali Khamenei, has rejected holding negotiations with the United States over a nuclear deal after receiving a letter from President Donald Trump calling for such talks.

With sanctions squeezing its economy, Iran is exploring the possibility of talks with the United States while resisting pressure to make major concessions. But he believes Iran has "no choice but to negotiate" with the United States.