Iran on Tuesday condemned US "interference" in its domestic affairs, after the State Department criticised last week's presidential election in the Islamic republic as neither free nor fair.
Ultraconservative cleric Ebrahim Raisi scored 62 percent of the vote in Friday's election, with more than half the voters staying away after many political heavyweights had been barred from the race.
The US State Department said the following day that it regretted that Iranians were unable to take part in a "free and fair electoral process".
"We consider this statement as an example of interference in Iran's internal affairs," government spokesman Ali Rabiei said, adding: "We condemn it.
"The US government is not in a position to comment on the electoral process in Iran or any other country," he said.
Iran and the United States have been sworn enemies for more than 40 years.
Tensions between them soared after then US president Donald Trump unilaterally withdrew from a key nuclear deal in 2018 and imposed crippling sanctions.
Trump's successor Joe Biden favours rejoining the nuclear agreement and the remaining parties to the accord are engaged in negotiations in Vienna to try to salvage it.
Raisi, seen as close to supreme leader Ayatollah Ali Khamenei, who holds ultimate political power in Iran, said on Monday he would not allow the negotiations to drag on.