Trump greatest threat to democracy: Navy Seal who killed Osama Bin Laden

US President Donald Trump's attacks on the news media represent the "greatest threat" to democracy, the retired Navy SEAL, who oversaw the killing of Osama bin Laden and the capture of Saddam Hussein, has said.

William McRaven's remarks on Sunday came after Trump derided the retired Navy SEAL and Special Operations commander as a "Hillary Clinton fan" and an "Obama backer".

Trump also suggested that the four-star admiral, who recently left his post as chancellor of the University of Texas amid a battle with chronic lymphocytic leukemia, should have caught bin Laden faster.

"Wouldn't it have been nice if we got Osama bin Laden a lot sooner than that, wouldn't it have been nice?" Trump told Fox news.

"I did not back Hillary Clinton or anyone else. I am a fan of President Obama and President George W Bush, both of whom I worked for. I admire all presidents, regardless of their political party, who uphold the dignity of the office and who use that office to bring the nation together in challenging times," McRaven said.

McRaven oversaw the May 2011 covert raid of the US Navy Seals which killed former Al-Qaeda leader bin Laden in a compound in Abbottabad in Pakistan. He also supervised the capture of former Iraqi President Saddam Hussein during his 37 years in the US military.

"I stand by my comment that the President's attack on the media is the greatest threat to our democracy in my lifetime," McRaven told CNN, referring to remarks he made about Trump last year.

"When you undermine the people's right to a free press and freedom of speech and expression, then you threaten the Constitution and all for which it stands," he said.

Trump coined the term 'Fake News' during his presidential campaign, targeting media houses and has been repeatedly using it for "biased" news coverage. The term is now popularly related to news one does not agree with.

He has also announced the 'Fake News Awards' for the "very corrupt and dishonest" press for "bad reporting".

McRaven's comments escalated a war of words that began last year when McRaven called Trump's description of the news media as the "enemy of the people" the greatest threat to American democracy he had ever seen.

In August, McRaven issued a stunning rebuke of Trump in an op-ed published in the Washington Post, writing that through his actions, the US President "embarrassed us in the eyes of our children, humiliated us on the world stage and, worst of all, divided us as a nation".

Former CIA deputy director Michael Morrell pointed out on Twitter that McRaven's forces had nothing to do with locating bin Laden.Morrell said it was the CIA that did the "finding" and McRaven's forces that did the "getting", moving out within days of receiving the order.

The president's remarks about McRaven came amid broader questions about Trump's relationship with military matters.

During a recent trip to France, the president did not attend a ceremony commemorating the centenary of World War I because of the rain, with the White House saying his helicopter couldn't fly in the inclement weather and a motorcade would have caused too much traffic.

Trump also has been criticised by his political opponents for not visiting either Afghanistan or Iraq in the first two years of his presidency.

He, however, said he was planning to visit the two countries."I think you will see that happen. There are things that are being planned. We don't want to talk about it because of - obviously because of security reasons and everything else," he said in an interview.