President Donald Trump will skip a weekend summit of North, South and Central American leaders to oversee his administration’s response to the situation in Syria, the White House announced Tuesday.

“At the President’s request, the Vice President will travel in his stead,” press secretary Sarah Huckabee Sanders said in a statement. “The president will remain in the United States to oversee the American response to Syria and to monitor developments around the world.”

The announcement came a day after the president called an apparent chemical attack by Syrian President Bashar al-Assad’s military “barbaric,” adding the United States “cannot allow atrocities like that,” Trump said during a Cabinet meeting with his top national security officials seated around him.

“It was atrocious. It was horrible. This is about humanity and it can’t be allowed to happen,” Trump told reporters at the White House.

“Nothing is off the table,” he said when asked specifically about the possibility he would order a second round of U.S. military strikes in the conflict-torn country in a year. He ordered 59 Tomahawk cruise missiles to be fired at a list of Assad military targets last spring; experts concluded, however, they had little effect and did not alter Assad’s behavior or decision-making.

The summit would have put Trump face-to-face with Central and South American officials he has sharply criticized over immigration into the United States. The list of South and Central Americas leaders slated to attend who Trump has panned includes the leaders of Mexico, Honduras and Cuba.

Also slated to participate is Canadian Prime Minister Justin Trudeau, who was close with former President Barack Obama and who Trump has called on to alter his country’s trade practices. In Pence, the leaders will find a more conventional politician likely to deliver more traditional diplomatic messages.

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