John McCain, the senior Republican senator and Vietnam War hero, has described US President Donald Trump's fiery phone conversation with Australian Prime Minister Malcolm Turnbull as "unneccessary and frankly harmful".
Senator McCain pointed to Australia's long history of standing side-by-side with US troops in wars across the world and revealed he'd called Ambassador to the US Joe Hockey to express his unwavering support for the US-Australian alliance.
The former presidential candidate also pointed to the importance of having US marines based in the Northern Territory and the close intelligence relationship the nations share.
"Australia, they fought alongside us in wars including losing over 500 brave Australians in the Vietnam War, which some of us remember," Senator McCain told reporters on Capitol Hill.
Questions marks over the strong relationship between the US and Australia surfaced after the Washington Post reported on Wednesday that Mr Trump had abruptly ended a phone call with Mr Turnbull last weekend.
The tension flared over an asylum seeker deal Mr Turnbull negotiated with former president Barack Obama last year for refugees held on Manus Island and Nauru be resettled in America.
Mr Trump, in a tweet, described it as a "dumb deal" and raised the prospect of it not going ahead.
In Saturday's phone call, Mr Trump allegedly told Mr Turnbull the refugees could be the "next Boston bombers" and the conversation was "the worst call by far" in what was a day of calls with world leaders.
"My view is it was an unnecessary and frankly harmful open dispute over an issue which is not nearly as important as the US-Australian co-operation," Senator McCain said.
Under the refugee deal negotiated between Mr Turnbull and Mr Obama last year, Australia would accept refugees from central America in return for the US taking the refugees held on Manus Island and Nauru.
