Iran's Supreme Leader Ayatollah Ali Khamenei is saying his country will not enter into talks with the United States outside of the nuclear deal with world powers.

In comments published on his website Wednesday, Khamenei said: "We approved talks with the United States about nuclear issue specifically. We have not allowed talks with the U.S. in other fields and we not negotiate with them."

Khamenei is quoted as saying any other talks would be "a tool for penetration and imposing their demands."

On Tuesday, Iranian President Hassan Rouhani signaled that Iran is ready to hold talks with the world powers on ways to resolve Syria's civil war, providing such negotiations can secure peace and democracy in the conflict-torn country. Iran supports embattled President Bashar Assad, whom the U.S. opposes.