Washington: US President Donald Trump on Tuesday claimed Iran is seeking to develop missiles that can strike the United States -- long-range weapons technology that only a limited number of countries possess.

"They've already developed missiles that can threaten Europe and our bases overseas, and they're working to build missiles that will soon reach the United States of America," Trump said during his State of the Union address.

He added that he wanted to solve the confrontation with Iran through diplomatic means but warned that he would never allow Tehran to develop nuclear weapons.

"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,'" Trump said in his State of the Union speech.

"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, which they are by far, to have a nuclear weapon."

In 2025, the US Defence Intelligence Agency said Iran could potentially develop a militarily viable intercontinental ballistic missile by 2035 "should Tehran decide to pursue the capability," but did not say if it had made such a decision.

Tehran currently possesses short- and medium-range ballistic missiles with ranges that top out at about 1,850 miles (3,000 kilometers), according to the US Congressional Research Service.

The continental United States is more than 6,000 miles from Iran's western tip.

Washington and Tehran have concluded two rounds of talks aimed at reaching a deal on Iran's nuclear program to replace the agreement that Trump tore up during his first term in office.

The United States has repeatedly called for zero uranium enrichment by Iran but has also sought to address its ballistic missile program and support for armed groups in the region -- demands Iran has rejected.

Trump has sent a massive US military force to the Middle East, deploying two aircraft carriers as well as more than a dozen other ships, a large number of warplanes and other assets to the region.

He has repeatedly threatened to strike Iran if negotiations fail to reach a new agreement. Talks with Tehran are currently set to continue on Thursday.