TEHRAN - Washington is willing to speak with Iran "with no preconditions", US Secretary of State Mike Pompeo said on Sunday, but Iran dismissed the offer as wordplay.

"We are prepared to engage in a conversation with no preconditions. We are ready to sit down with them," Pompeo told a joint news conference in Switzerland with Swiss Foreign Minister Ignazio Cassis.

"The American effort to fundamentally reverse the malign activity of this Islamic Republic, this revolutionary force, is going to continue," Pompeo added.

Iran's foreign ministry spokesman Abbas Mousavi responded by saying: "The Islamic Republic of Iran does not pay attention to wordplay and expression of hidden agenda in new forms."

Meanwhile, Iran's President Hassan Rouhani presented the offer of talks with no preconditions as a sign of Iran's strength.

"The enemies sometimes say they have conditions for negotiations with Iran ... but in recent weeks they said they have no conditions. They threatened us as if they were a military superpower, but now they say they do not seek a war," he said.

Rouhani also said it was up to the US to return to the negotiating table and resume compliance with the 2015 nuclear deal with world powers to curb Tehran's nuclear programme in return to the lifting of sanctions.

"The other side that left the negotiating table and breached a treaty should return to normal state," he said in comments reported on the government website.(FA)