Iran hit out at US threats of military action in case of nuclear diplomacy failure, saying that the fevered partisanship of US politics is damaging the country’s foreign policy.

Iran hit out at US threats of military action in case of nuclear diplomacy failure, saying that the fevered partisanship of US politics is damaging the country's foreign policy.

"Political partisanship and competition have taken US foreign policy hostage," foreign ministry spokeswoman Marzieh Afkham said, calling Obama's remarks "repetitive and baseless".

These claims are "showing the uncertainty and depth of confusion of American officials in determining their national interests," Afkham said, according to the official IRNA news agency.

The comments in Tehran came after US President Barack Obama said in a letter that all options remain on the table against Iran.

Obama said in a letter to Jerrold Nadler, a Democrat who has announced his support for the deal, that the agreement is good for America, Israel and the Middle East in general.

"We have a wide array of unilateral and multilateral responses that we can employ if Iran fails to meets its commitments," Obama said.

"All of the options available to the United States -- including the military option -- will remain available through the life of the deal and beyond," he added.

Iran and six world powers led by the US struck a historic deal last month on Tehran's nuclear program but it is undergoing a bruising review in Congress.