Retired U.S. Navy Cmdr. Kirk Lippold said Friday that renewed American combat operations against Iran appear increasingly likely, arguing Tehran has shown no willingness to abandon its nuclear program through diplomacy.

Speaking on “America Reports,” Lippold said it is now “a matter of not if, but when the United States is going to recommence combat operations.”

“The president has given the Iranians every opportunity to come to the right answer through diplomatic channels,” Lippold said. “Iran will not give up their nuclear program.”

Lippold’s comments came shortly after Secretary of State Marco Rubio said negotiators had seen some progress in talks with Tehran but cautioned that “there’s more work to be done.”

“The President would prefer to do a good deal,” Rubio said during remarks at a NATO conference in Sweden.

Lippold, the former commanding officer of the USS Cole, suggested President Donald Trump is using ongoing negotiations to give the U.S. military time to “rearm, refuel, and be ready for combat operations.”

He also argued the administration should avoid publicly declaring negotiations over in order to avoid giving Iran time to prepare.

The remarks came as Iranian state media reported that negotiators were not discussing Tehran’s nuclear program at the moment, while a Qatari team remained in Tehran to support talks with the United States.

Yesterday’s Fox News Digital live blog offers additional coverage of the Iran conflict.