WASHINGTON, DC (CBS News/AP) — With days left to make a decision about whether the United States will remain a part of the Iran nuclear deal, President Donald Trump is accusing former Secretary of State John Kerry of conducting “illegal shadow diplomacy” to preserve the nuclear agreement that curbs Iran’s development of a nuclear arsenal.

“He was the one that created this MESS in the first place,” Trump tweeted on Monday of the “very badly negotiated” Iran deal.

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The president said he will announce his decision on the Iran nuclear deal on Tuesday.

In a tweet Monday, Trump says, “I will be announcing my decision on the Iran Deal tomorrow from the White House at 2:00pm.”

Jerusalem Embassy

Elsewhere in the Middle East, Nneither President Trump nor Vice President Mike Pence planned to be in attendance when the U.S. opens its embassy in Jerusalem next week.

The White House says Trump is instead sending a high-level delegation to the ceremony marking the formal recognition by the U.S. of Jerusalem as Israel’s capital. Trump ordered the move last year, fulfilling a key campaign promise but drawing condemnation from many U.S. allies, who say the move makes it more difficult to achieve peace between Israelis and Palestinians.

The White House says Deputy Secretary of State John Sullivan is leading the delegation, joined by Treasury Secretary Steven Mnuchin and the president’s daughter and son-in-law, White House aides Ivanka Trump and Jared Kushner.

Iran Deals And Dealing

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The Boston Globe reported Friday that Kerry recently sat down with Iranian Foreign Minister Javad Zarif to discuss ways to salvage the Obama-era deal. The Globe, citing a person briefed on the meetings, reported that it was the second time in roughly two months the two had met to talk strategy about the future of the agreement. The two had worked together for two years along with other Obama administration negotiators to reach the agreement to freeze Iran’s nuclear development.

Zarif recently told CBS’ “Face the Nation” however that Iran is “ready” to restart its controversial nuclear program if the Trump administration leaves the 2015 Iran nuclear deal and reinstates sanctions.

“We have put a number of options for ourselves, and those options are ready, including options that would involve resuming at a much greater speed our nuclear activities,” Zarif said.

The newspaper adds that Kerry had also met with German President Frank-Walter Steinmeier and French President Emmanuel Macron, a vocal proponent of brokering a separate, more comprehensive deal to quell the U.S.’ concerns.

In response to Trump’s claims, a Kerry spokesperson said in a statement to CBS News, “I think every American would want every voice possible urging Iran to remain in compliance with the nuclear agreement that prevented a war.”

The statement added, “Secretary Kerry stays in touch with his former counterparts around the world just like every previous Secretary of State. 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.”

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