(FOX NEWS) — President Donald Trump said Tuesday that the United States is maintaining a firm stance in negotiations with Iran over its nuclear program, underscoring what he described as recent military success and economic leverage ahead of his trip to China.

Speaking to reporters before leaving, Trump drew a clear red line against Tehran obtaining nuclear weapons.

“Well, we’re going to see, and we’ll be thinking about it on the flight, and we’ll be thinking about it for the next little while,” Trump said on Iran.

The president went on to highlight that the U.S. had “beaten their military very soundly. That’s over with. The blockade is very effective. It’s been 100% effective,” he said.

“And one way or the other, it’s going to work out very well. It’s going to work out very well,” he said.

On the topic of oil and the economy, Trump said the U.S. was going to have “so much oil.”

“You’re going to have a gusher of oil like you’ve never had before. So when oil goes up a little bit, I thought it would go up much more,” he added.

Shifting to the key issue of Iran’s nuclear program, which has stalled talks between the two nations, Trump insisted:

“Iran cannot have a nuclear weapon.”

“They will not have a nuclear weapon. They know that. They’ve agreed to that.”

“And that’s not what they said to me when it came to — we don’t play games. They’re not going to have a nuclear weapon,” he said.