Lady Gaga and John Legend are leading the celebrity outcry after Donald Trump stunned the media by explaining his reasons for delaying a response to the violence that broke out at a white supremacy rally at the weekend.

The U.S. leader was speaking to the press at Trump Tower in New York on Tuesday (15Aug17) when he was asked about the deadly events in Charlottesville, Virginia.

The usually quick-to-tweet President defended his decision to delay his condemnation of neo-Nazis and white supremacists after the tragic events, which cost one counter-protester her life, explaining he was waiting to learn all the facts.

He then stunned fans and critics alike by stating, "I think there’s blame on both sides and I have no doubt about it. What about the alt-left that came charging at, as you say, the alt-right? Do they have any semblance of guilt...? I think they do."

Gaga, Legend and John Mayer were among the first to jump on Twitter and attack Trump, with the Poker Face singer asking fans: "Do you think @realDonaldTrump @POTUS saying 'both sides are to blame' in #Charlottesville makes him a racist supporter? Yes or no?"

Legend added: "One of the most transparent lies Trump told today is that he likes to wait for the facts before he makes a statement. Hahahahahaahaha... It's still hard for me to believe so many people voted for this idiot. This is your fault too."

And Mayer wrote: "The infrastructure that will be remembered today is the one the people will build so that we all become the president that this man is not."

There was also outrage from Demi Lovato, Ellie Goulding, Elizabeth Banks, Dax Shepard, Mia Farrow, Barbra Streisand, J.K. Rowling, and Patricia Arquette, who tweeted: "There's one thing this President is good at - he is the best at being the worst."

Meanwhile, Captain America Chris Evans really challenged Trump, raging online: "Is anyone else watching this (press conference)?!? Wow… it's like watching a train wreck!! 'Before I make a statement I need the facts'?! Since when?? Wow. Wow. Wow... This is insane."

"That press conference kinda just blew up my brain. Everyone should watch that entire thing from beginning to end. It's truly shocking... His brain just isn't good enough... Seriously. EVERYONE needs to watch that press conference in its entirety. He does everything flawlessly wrong. It's a stunning disaster."

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