Iran's Supreme Leader Ayatollah Ali Khamenei on Wednesday rejected holding negotiations with the United States over a nuclear deal, as a letter was delivered from U.S. 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.Since returning to the White House in January,

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.