Speaking on MSNBC, Michael Cohen said the president would probably fight the election result until January and beyond from the comfort of his Florida escape.
“I would not be shocked if there is no concession speech at all. My theory is that at Christmas time he goes to Mar-a-Lago. I think he will stay there through the inauguration. I would not be shocked if he will not show up to the inauguration either,” Mr Cohen said.
“He cannot let the camera look at him and basically pull down the curtain and see the wizard standing beside. He is just a loser and it is killing him and, right now, what is going on in the White House is nothing but finger-pointing.”
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Mr Trump has given no indication of conceding the election following projections that Mr Biden would become the 46th president of the United States.
As the president-elect gave a national address to the nation and began picking the first official posts to his incoming administration, the Trump administration called a “lid” on both Saturday and Sunday as the president spent his weekend playing golf.
While Mr Trump hasn’t appeared in-person since the election results were announced, he was seen in video footage from the golf course posing with a bride on her wedding day.
Mr Trump told club members “we’ve got a long way to go”, eluding to the legal battle ahead as he contests the results in key states, while tweeting claims the election was stolen and he won by “A LOT”
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His first official in-person comments will be made on Fox News on Sunday night, where he is not expected to concede after tweeting the interview would focus on what he called “the Mail-In Ballot Hoax!”
Asked what the president planned on doing post-presidency, Mr Cohen said he would fight the result of the election even after Mr Biden’s inauguration in January — possibly from a “Trump network” or media company, which was the goal of the first election bid.
“Donald Trump cannot accept the fact that he lost. To him, it is like calling him a loser, which is the worst thing in the world that you can call him,” Mr Cohen said.
“He will fight this not just until January when he is now required to leave and go wherever he has to go, but he will do things post leaving that will make things very difficult for the Biden administration.”