European diplomats and politicians paid close attention to President Donald Trump's State of the Union speech on Tuesday because of his references to Iran and its nuclear program.

"We are in negotiations with them; they want to make a deal, but we haven't heard those secret words, 'we will never have a nuclear weapon,'" the president said. "My preference is to solve this problem through diplomacy. But one thing is certain, I will never allow the world's number one sponsor of terror to have a nuclear weapon."

Eyes in Europe are on the upcoming negotiations in the Swiss city of Geneva on Thursday between a U.S. delegation led by Special Envoy Steve Witkoff and Iranian negotiators. The talks seek an agreement on a framework for a new nuclear deal.

While President Trump has said he wants a diplomatic solution, there is also the possibility that the United States could resort to military action against Iran.

For weeks, U.S. military assets including strike aircraft, dozens of cargo and tanker flights and at least two aircraft carrier strike groups have congregated in the Middle East region.

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Both the U.S. and Iran indicated war would be a possibility if nuclear talks don't reach a satisfactory stage.

“We are prepared for diplomacy, and we are prepared for negotiation as much as we are prepared for war,” Iran's foreign minister Abbas Araghchi said last week.