WASHINGTON — Two inconclusive rounds of negotiations between Iran and the United States have heightened expectations that military action could be on the horizon.

For more than three hours on Tuesday, negotiators for the two countries held Oman-mediated indirect talks in the Swiss city of Geneva aimed at reaching an agreement that would avert the strikes President Donald Trump has threatened if no deal is reached. Iranian Foreign Minister Abbas Araghchi touted “good progress” from the talks, but Vice President JD Vance was more cautious, pointing out that Tehran had failed to acknowledge US red lines. Vance said Trump’s preference is for a deal, but that he may eventually determine that “diplomacy has reached its natural end."

The two sides have yet to agree on the scope of the negotiations. Iran has demanded the talks be confined to its nuclear program, while the Trump administration has said it’s seeking a deal that also addresses its ballistic missile program and support of regional militias.

On the nuclear issue alone, Washington and Tehran are at major odds. Trump said Friday that his administration won’t accept “any enrichment” from Iran, which has long insisted on its right to enrich uranium for what it says are peaceful purposes.