President Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE on Monday slammed former Secretary of State John Kerry John Forbes KerryThe Memo: Warning signs flash for Trump on debates Divided country, divided church TV ads favored Biden 2-1 in past month MORE for reportedly working to save the Iran nuclear deal.

“The United States does not need John Kerry’s possibly illegal Shadow Diplomacy on the very badly negotiated Iran Deal,” the president wrote on Twitter. “He was the one that created this MESS in the first place!”

The United States does not need John Kerry’s possibly illegal Shadow Diplomacy on the very badly negotiated Iran Deal. He was the one that created this MESS in the first place! — Donald J. Trump (@realDonaldTrump) May 7, 2018

Trump’s tweet comes after The Boston Globe reported last week that Kerry met Iranian Foreign Minister Mohammad Javad Zarif, who was Kerry's counterpart when he served as secretary of State, to speak about how to protect the accord. The newspaper also said Kerry has met with other world leaders, including French President Emmanuel Macron and German President Frank-Walter Steinmeier.

ADVERTISEMENT

The effort runs up against Trump’s self-imposed May 12 deadline for the United States to decide whether it will exit the Obama-era agreement.

A spokesperson for Kerry dismissed Trump's tweet, saying Americans "would want every voice possible urging Iran to remain in compliance with the nuclear agreement that prevented a war."

“Secretary Kerry stays in touch with his former counterparts around the world just like every previous Secretary of State,” the spokesperson told Fox News.

“Like America’s closest allies, he believes it is important that the nuclear agreement, which took the world years to negotiate, remain effective as countries focus on stability in the region.”

The accord, which provided Tehran sanctions relief in exchange for curbs to its nuclear program, was Kerry’s signature policy achievement at the State Department.

ADVERTISEMENT

But Trump has repeatedly railed against the deal since his presidential campaign, arguing it was negotiated poorly.

“The deal with Iran will go down as one of the most incompetent ever made. The U.S. lost on virtually every point. We just don't win anymore!” Trump said in September of 2015.

Zarif has publicly argued that Trump should remain part of the accord, saying it’s “all or nothing.”

“It's either all or nothing. European leaders should encourage President Trump not just to stay in the nuclear deal, but more importantly to begin implementing his part of the bargain in good faith,” Zarif said last month.

Updated at 11:20 a.m.