As Tehran asserts that it will not participate in a second round of in-person talks with U.S. negotiators in Islamabad, Pakistan, on Monday unless the naval blockade on Iranian ports is lifted, President Donald Trump is claiming that a peace deal is almost complete.

"I feel fine about it. The concept of the deal is done. I think we have a very good chance to get it completed," Trump told Axios in an interview on Sunday.

The president offered no details regarding what was in the deal.

Trump's comments to Axios were published just hours after he threatened to bomb all of Iran's power plants and bridges if the Iranians don't sign the deal.

“If the deal isn’t done, the deal that we made, then I’m going to take out their bridges and their power plants," Trump told Fox News in a separate interview. “If they don’t sign this thing, the whole country is going to get blown up.”

The president told ABC News' Jonathan Karl something similar Sunday.

"It’s going to be very good," Trump said. "They are either going to do it or they are going to have problems. We’ll see what happens."

The present ceasefire agreement is set to expire on Wednesday.

-ABC News' Nicholas Kerr

President Donald Trump said Sunday morning that the entire country of Iran would get “blown up” if leaders there don’t sign a deal with the U.S.

"If they don't sign this deal, the whole country is going to get blown up," Trump told Fox News, shortly after he wrote on his social media platform that talks would resume in Islamabad on Monday.

The president later told The New York Post that his advisers, special envoy Steve Witkoff and Jared Kushner, would be heading to Islamabad on his behalf.

The president did leave open the possibility that he could travel to Islamabad at some point, but gave no indication when.

“I would say maybe at a little bit later date. We have to see how it works out tomorrow,” he said.

-ABC News' Nicholas Kerr