WASHINGTON — President Trump has decided to attend a summit meeting of Pacific Rim leaders in the Philippines on Nov. 14, the White House said on Friday, a decision that will tack an extra day onto his already marathon tour of the region.

Speaking to reporters as he left the White House for Hawaii, the first leg of his trip, Mr. Trump said he planned to spend an extra day in the Philippines at the end of his 11 days on the road.

Later, the White House press secretary, Sarah Huckabee Sanders, confirmed that he would attend the East Asia summit, a meeting of leaders from Australia, Japan, China, Russia and other countries that his predecessor, President Barack Obama, had made a priority.

Mr. Trump’s earlier decision to skip the meeting had rattled officials in the region, who warned that it would raise questions about the United States’ commitment to Southeast Asia.