Iran's supreme leader Ayatollah Ali Khamenei said Wednesday that he would not permit negotiations with the United States beyond those that culminated in a nuclear deal with world powers in July.
"We allowed negotiation with the US only on the nuclear issue for certain reasons," Khamenei said in a speech. "In other areas we did not and will not allow negotiations with the US."
Khamenei charged that Washington only sought talks on a broader range of issues in a bid to impose its own policies on Tehran.
"US officials seek negotiation with Iran. Negotiation is a means of infiltration and imposition of their will," he said.
"The Iranian nation expelled this Great Satan, we barred their direct access and now we must not allow their indirect access and infiltration."
The comments from Khamenei, who has the final say on all matters of state in Iran, came after the US Congress began debate on Tuesday on the nuclear agreement reached with Iran.
President Barack Obama has just enough support in the US Senate to prevent the deal being blocked.
But a majority of lawmakers oppose the deal, backing Israeli claims that it does not do enough to prevent any possibility of Iran developing a nuclear weapon.
Iran rejects Israel's right to exist, a stance Khamenei reiterated on Wednesday.
"God willing, there will be no such thing as the Zionist regime in 25 years' time," the Iranian leader said.
"In the meantime, the spirit of struggle and jihad will not leave the Zionists a moment's peace."
Iran has always denied any ambition to acquire a nuclear weapon and Khamenei has himself said repeatedly that any such policy would be a violation of Islam.