The Kremlin, asked on Monday if Russia had held consultations with Iran before or after Tehran responded to a letter from U.S. President Donald Trump urging the country to negotiate a nuclear deal, said Iran formulates its own policy positions.

Iran's Supreme Leader Ayatollah Ali Khamenei said on Saturday that Tehran would not be bullied into negotiations, a day after Trump said he had sent a letter urging Iran to engage in talks on a new nuclear deal.

Asked if Moscow had consulted with Tehran before or after Trump's letter, Kremlin spokesman Dmitry Peskov told reporters:

"No. Iran is a sovereign country and independently formulates its position on key foreign policy issues. It is clear that very tense contacts are ahead."

Trump has previously said he would reimpose a policy of "maximum pressure" on Iran, aimed at preventing the country from building nuclear weapons, even as he has signalled openness to a new nuclear accord with Tehran.

Russia and Iran have drawn closer since the start of the war in Ukraine, with Tehran providing Moscow with drones.

Regarding possible talks on Tehran's nuclear program, Peskov said: "It is clear that Iran is seeking negotiations based on mutual respect, constructive negotiations."

"We, of course, for our part, will continue to do everything that depends on us, everything that is possible, in order to bring this process of settling the Iranian nuclear dossier into a peaceful direction."