U.S. Capitol Flag Is Lowered to Honor John McCain. At the White House, It’s Back Up.

WASHINGTON — The White House inexplicably flew the American flag at full-staff on Monday, after flying it at half-staff on Saturday night and Sunday in honor of Senator John McCain.

The lowering and raising of the flag amplified the division between President Trump and the longtime Republican senator, who died Saturday at 81. Mr. Trump offered his condolences on Saturday to Mr. McCain’s loved ones, but he has said nothing about Mr. McCain.

The president ignored questions about Mr. McCain and the flag before and after an announcement on trade policy late Monday morning.

Mr. McCain was one of few Republicans in Congress who pushed back against Mr. Trump and publicly criticized his style of leadership.

The status of the flag made the rounds on social media, fueling speculation that the height of the American flag at the White House and other federal buildings was the president’s attempt to insult Mr. McCain. Earlier in the day, Mr. Trump posted messages on Twitter about professional football and the golfer Tiger Woods.

A veterans’ group, VoteVets, criticized the president over the situation. “Donald Trump refuses to lower flag, for John McCain. As we said yesterday, Donald Trump is a pathetic, thin-skinned, self-centered, low-class, petty coward,” the group wrote in a Twitter post on Monday.

Presidents often issue proclamations after significant events, like a mass shooting or the deaths of important figures, specifying that flags should fly at half-staff and for how long at federal buildings, military posts and facilities abroad, like embassies. There has not been a proclamation about Mr. McCain.

It was not immediately clear that the flag at the White House was raised on Monday at the direction of the president, or if the flag is automatically fully raised absent a presidential proclamation to fly it at half-staff. The United States Flag Code provides for the lowering of the American flag on the day of the death of a member of Congress and the following day.

“Flag custom is always political by definition,” said Charles A. Spain, a director at the Flag Research Center. “The president has the ability to just reach out” and lower the flag.

The president previously issued a proclamation for flags to be lowered on the day that the Rev. Billy Graham was buried early this year. Mr. Trump made the proclamation on February 21, and Mr. Graham was buried in early March.

Flag policy has been a priority for Mr. Trump, even before he was president.

Mr. Trump has attacked players in the National Football League who kneel during the playing of the national anthem in a silent protest for civil rights, saying their actions were disrespectful to the flag and the United States military.

And in 2015, Mr. Trump criticized then-President Barack Obama for not lowering the flags soon enough after the shooting in Chattanooga, Tenn., where five military members were killed.

Mr. Obama issued a proclamation in honor of the Chattanooga victims after Republicans criticized his inaction.

Mr. Trump, however, was similarly criticized earlier this summer for his delay in honoring the victims of a shooting in a newsroom in Annapolis, Md. Days after the shooting, Mr. Trump called for flags to be flown at half-staff.