Iran's reformist President Mohammad Khatami has urged his allies in the Iranian parliament to abandon the search for better relations with the US given the growing US belligerence towards Tehran.
Mr Khatami, a moderate cleric who broke years of stalemate between the two states when he made a dramatic overture to the US after his 1997 election, said he was put off by the "humiliating and threatening" tone used by US leaders when speaking of Iran.
"When a big power uses a militant, humiliating and threatening tone to speak to us, our nation will refuse to negotiate or show any flexibility," he said at a meeting with members of parliament, where his allies hold a majority.
Iran's Supreme National Security Council, headed by Mr Khatami, has reportedly ruled out negotiations with the United States in reaction to charges by President Bush that Iran is part of an "axis of evil."
Tehran and Washington broke ties after Islamic militants seized the US Embassy in Iran in the wake of the 1979 Islamic revolution which toppled the US-backed shah.
In a televised address to American people after his election, Mr Khatami called for greater contacts between the two nations to crack the "wall of mistrust" between them.
Relations have improved between Europe and Iran in recent years resulting in an increase in trade between the two.