President Trump warned at a campaign rally in Dubuque, Iowa, on Sunday that the United States may have to deliver additional military blows to Iran if diplomatic efforts fail.

"The only reason why I'm not finished with Iran is I want to be nice," Trump said. "I want to try and save all those lives if I can. But at some point we're going to have to give them the hammer."

The comments came just days before Tuesday's midterm elections and amid ongoing tensions following U.S. and Israeli strikes that began February 28. Trump said previous operations had already destroyed much of Iran's nuclear capabilities, including ships and planes.

He specifically mentioned the suspected underground nuclear site known as Pickaxe Mountain as a potential target that could be struck quickly. Trump told the crowd that the U.S. had plans ready and could act in minutes if necessary.

The president noted he had spoken with Israeli Prime Minister Benjamin Netanyahu over the weekend. Reports indicate Netanyahu has pushed for renewed strikes after the elections, while Trump has expressed a preference for allowing more time for negotiations.

Trump has repeatedly stated that the conflict will end soon, either through a deal or decisive U.S. action. He has framed the prior strikes as a major success that left Iran with limited options.

Iranian officials have warned that any renewed fighting could last longer than the initial round and would not be limited geographically. Back-channel diplomatic efforts involving Qatar have continued in an attempt to reach an agreement before further escalation.

The rally drew supporters focused on the midterm contests, with Trump using the platform to highlight his administration's firm stance against Iranian threats.