“Many Trump Fans & Signs were outside of the @FoxNews Studio last night in the now thriving (Thank you President Trump) Bethlehem, Pennsylvania, for the interview with Crazy Bernie Sanders,” Mr Trump tweeted on Tuesday evening.
“Big complaints about not being let in – stuffed with Bernie supporters. What’s with @FoxNews?”
The president’s claim his supporters were barred from the event was contradicted by local media, who reported a range of political groups were in the audience, including Trump supporters.
“So weird to watch Crazy Bernie on @FoxNews,” Mr Trump had tweeted earlier. “Not surprisingly, @BretBaier and the ‘audience’ was so smiley and nice. Very strange, and now we have @donnabrazile?”
The morning after the event, Fox & Friends, a news show which consistently supports Mr Trump and his agenda, invited a tax expert to cast reservations about Mr Sanders’ healthcare plan.
Mr Trump later renewed his attack on Mr Sanders, who piled more pressure on the president to release his tax returns after earlier this week making public his own.
“Bernie Sanders and wife should pay the Pre-Trump Taxes on their almost $600,000 in income,” Mr Trump tweeted.
“He is always complaining about these big TAX CUTS, except when it benefits him. They made a fortune off of Trump, but so did everyone else – and that’s a good thing, not a bad thing!
“I believe it will be Crazy Bernie Sanders vs. Sleepy Joe Biden as the two finalists to run against maybe the best Economy in the history of our Country (and MANY other great things)! I look forward to facing whoever it may be. May God Rest Their Soul!”
It is not clear why Mr Trump signed off using a phrase usually reserved for the dead.