President Donald Trump delivered an ominous warning to Iran Tuesday morning regarding the country's nuclear weapons program.

"They restart their nuclear program, they will have bigger problems than they have ever had before," Trump said.

Trump has been very critical of the Iran nuclear deal that was signed between Iran and a group of several countries, including the United States, in 2015. He was asked about it during a brief press availability in the Oval Office with French President Emmanuel Macron.

"It seems no matter where you go, especially in the Middle East, Iran is behind it. Wherever there is trouble. No matter where you have it, Iran is behind it," said Trump, who will discuss the Iran deal and the Paris climate accord with Macron during meetings Tuesday.

"The Iran deal is a disaster."

Macron also weighed in on the matter, first speaking in French before summarizing his answer in English.

"The Iran deal is an important issue. We'll discuss that but we have to take it as a part of a broader picture, which is security in the whole region and we have upcoming things in Iraq," he said.

During an interview broadcast over the weekend, Macron said the U.S. should stay in the Iran deal if there is no better way to prevent Iran from restarting its nuclear weapons program.