President Donald Trump has ordered American flags at US buildings lowered to half-staff for senator John McCain until his burial on Sunday.
Mr Trump's proclamation came just hours after the White House flag had been returned to full-staff, drawing complaints from both sides of the political spectrum.
Mr Trump, who had traded bitter criticism with Mr McCain since before the election, declared his order "a mark of respect".
At the same time, he said it would be vice president Mike Pence and other officials who would represent the administration at Mr McCain's funeral services.
"Despite our differences on policy and politics, I respect Senator John McCain's service to our country and, in his honour, have signed a proclamation to fly the flag of the United States at half-staff until the day of his interment," Mr Trump said in a statement.
The statement came two days after Mr McCain died at 81 from brain cancer - and after objections at Mr Trump's silence from politicians and others, including the American Legion, which demanded that he do more to honour the Vietnam War hero and six-term senator.
Mr Trump initially tweeted condolences to Mr McCain's family, but made no mention then of the Arizona Republican with whom he feuded for years.
Even as flags remained at half-staff on Monday at the capital, the Washington Memorial and elsewhere, the White House flag was raised. That seemed to be the breaking point for a key Trump constituency, veterans.
"On the behalf of The American Legion's two million wartime veterans, I strongly urge you to make an appropriate presidential proclamation noting Senator McCain's death and legacy of service to our nation, and that our nation's flag be half-staffed through his internment," said a statement to Mr Trump from Denise Rohan, the organisation's national commander.
By the end of the day, Mr Trump had done just that, with no immediate explanation from the White House.
But evidence of Mr Trump's feud with Mr McCain remained. People close to Mr McCain and the White House said the family had requested that Mr Trump stay away from the week's services and ceremonies, which will culminate with Mr McCain's burial at the US Naval Academy in Annapolis, Maryland.
Mr Trump said vice president Pence would address a ceremony at the US capital on Friday. Others in the administration - chief of staff John Kelly, defence secretary James Mattis and national security adviser John Bolton - will also represent the administration.
With the proclamation and statement, Mr Trump was conforming to standard protocol when a prominent member of government dies.