People close to President Donald Trump say he is in the early stages of dementia, MSNBC’s Joe Scarborough has said.

During his political commentary show Morning Joe, Mr Scarborough said Mr Trump is “completely detached from reality.”

“You have somebody inside the White House that the New York Daily News says is mentally unfit,” Mr Scarborough said.

“That people close to him say is mentally unfit, that people close to him during the campaign told me had early stages of dementia”.

To partially explain the reason behind Mr Trump's many falsehoods, reporters covering Mr Trump - such as Maggie Haberman of the New York Times - have said the President has a lifelong habit of attempting to create and sell his own version of reality.

Mr Trump has pushed conspiracy theories and has continually changed his story on several issues, such as whether he was the voice on Access Hollywood recordings making lewd comments about women. He has admitted in the past that it was him.

Mr Trump took aim at Mr Scarborough earlier this week, appearing to call for a probe into the death of a staff member who was found in the former politician's office in 2001.

In a tweet following NBC's firing of host Matt Lauer over sexual misconduct claims, the President tweeted: “So now that Matt Lauer is gone when will the Fake News practitioners at NBC be terminating the contract of Phil Griffin? And will they terminate low ratings Joe Scarborough based on the 'unsolved mystery' that took place in Florida years ago? Investigate!”

Mr Scarborough responding by saying the President is “not well”.

Mr Scarborough has been the conservative voice of Morning Joe for a decade and served as a US congressman from Florida from 1995 to 2001.

He and his co-host Mika Brzezinski used to be friends with Mr Trump, who regularly called their programme during the early days of his candidacy.