WASHINGTON, DC (CBS News) — President Trump is no longer heading to the Summit of the Americas this weekend and instead will be staying in the U.S. to focus on Syria in the wake of the suspected chemical attack in the Syrian city of Douma. Vice President Mike Pence is slated to take his place instead.

White House Press Secretary Sarah Huckabee Sanders released a statement on the change of plans early Tuesday morning.

“President Trump will not attend the 8th Summit of the Americas in Lima, Peru or travel to Bogota, Colombia as originally scheduled. At the President’s request, the Vice President will travel in his stead. The President will remain in the United States to oversee the American response to Syria and to monitor developments around the world.”

The regional summit is seen as the leading forum for projecting U.S. leadership in Latin America and the Caribbean with U.S. presidents participating in all seven previous gatherings.

After leaving Columbia, Trump was due to travel to his Mar-a-Lago estate where he was planning to host Prime Minister of Japan Shinzo Abe for talks on North Korea.

Trump told reporters on Monday during a Cabinet meeting that the administration would be making a “major” decision on Syria within the next 24 to 48 hours.

“This is about humanity, we’re talking about humanity, and it can’t be allowed to happen,” he said. “We’ll be making that decision very quickly, probably by the end of today. We cannot allow atrocities like that.”

Trump said that the administration is still “studying” the situation in Syria closely and is talking to military leaders about an appropriate response.

After a sarin chemical attack in Syria in April last year, Trump ordered a missile strike on a Syrian military target in Shayrat, about 50 miles due south of the village that was hit in a gas attack.

On Monday, Defense Secretary James Mattis said he would not “rule out anything” as a response against Syrian President Bashar Assad. Trump echoed the secretary’s response to taking military action, saying “nothing’s off the table.”

Secretary Sanders also faced questions about Special Counsel Robert Mueller in the wake of Monday’s raid at the president’s personal attorney Michael Cohen’s home and office.

Cohen is under investigation for possible bank fraud, campaign finance violations, and other potential crimes.

Mueller’s office supplied information leading up to the raids, raising renewed speculation that Trump might try to fire Mueller. Most legal experts agree the president would have to order Deputy Attorney General Rod Rosenstein to fire the special counsel, and Rosenstein could refuse.

Sanders on Tuesday indicated that Trump could do it himself.

“He certainly believes he has the power to do so,” she said.

But leaders in Trump’s party warned that would be a bad idea.

“I think it would be political suicide to do that,” Senator Charles Grassley (R-IA) said. “I think he should say very little and he should let the investigation go forward.”

CBS News’ Katiana Krawchenko contributed to this report.

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