US Defense Secretary Mark Esper has defended President Donald Trump over claims he belittled the sacrifice of US war veterans.
Esper's statement on Friday followed an article posted on The Atlantic magazine's website on Thursday by editor-in-chief Jeffrey Goldberg, which cited four unnamed sources claiming Trump called two Republican leaders who fought in major wars "suckers" and "losers".
"President Trump has the highest respect and admiration for our nation's military members, veterans and families. That is why he has fought for greater pay and more funding for our armed forces," Esper said.
The Atlantic article includes unconfirmed claims that Trump did not want to grant state honours to late Arizona Senator John McCain following his death from brain cancer in 2018.
It alleges that Trump said: "We’re not going to support that loser’s funeral," and grew angry when flags were lowered to half-mast in McCain's honour. "What the f**k are we doing that for? Guy was a f***ing loser," he supposedly said.
Three sources also claimed that Trump called late President George H W Bush a "loser" for being shot down and taken prisoner as a US Army Air Force pilot during the Second World War.
Another source alleges that during a 2017 visit to the war graves at Arlington National Cemetery in Virginia, outside Washington DC, he said to then-homeland security secretary John Kelly, "I don’t get it. What was in it for them?" as the two stood by the grave of Kelly's son Robert, who was killed in Afghanistan in 2010. Kelly himself declined to comment on that claim.
At a press conference on Friday, Democratic candidate Joe Biden seized on the Atlantic article to accuse Trump of being unfit for office.
"If what is written in The Atlantic is true, it’s disgusting," Biden said. "It affirms what most of us believe to be true, that Donald Trump is not fit to be the commander in chief."
“When my son volunteered and joined the US military … and went to Iraq for a year, won the Bronze Star and other accommodations, he wasn’t a sucker,” he added in reference to his late son Beau.
Former secretary of state Hillary Clinton, who lost the 2016 presidential election to Trump, tweeted that she was not surprised at the allegations against Trump.
In a series of tweets on Thursday evening, Trump called the Atlantic story "fake news" and denied he had ever shown disrespect for McCain, despite their political disagreements.
McCain was a leading supporter of the US invasions of Iraq and Afghanistan and the 2011 bombing of Libya, and pushed for war with Iran.
Former Navy ground-attack pilot McCain's claims of torture as a prisoner of war in Vietnam were denied in 2008 by his former guard in captivity Nguyen Tien Tran.
In August, sources claimed Trump was planning to replace Esper if the president is re-elected in November - and that the Pentagon chief was planning to step down in any case over policy differences between the two.