Johnny Depp is sorry for joking about assassinating US President Donald Trump.

The 54-year-old actor made the controversial quip during an appearance at Glastonbury festival's new Cineramageddon tent, when he referenced President Abraham Lincoln's 1865 assassination at the hands of actor John Wilkes Booth and said: ''Can we bring Trump here? I think he needs help and there are a lot of wonderful dark, dark places he could go.

''It is just a question - I'm not insinuating anything. By the way, this is going to be in the press. It will be horrible. I like that you're all part of it. But when was the last time an actor assassinated a president?

''I want to clarify, I'm not an actor. I lie for a living. However, it's been a while and maybe it is time. Thank you so much for having me here.''

However, TMZ reports he later backtracked, saying: ''It did not come out as intended, and I intended no malice. I was only trying to amuse, not to harm anyone.''

Trump's administration slammed Johnny's comments, saying: ''President Trump has condemned violence in all forms and it's sad that others like Johnny Depp have not followed his lead.

''I hope that some of Mr Depp's colleagues will speak out against this type of rhetoric as strongly as they would if his comments were directed to a Democrat elected official.''

The 'Dark Shadows' star isn't the only famous face to have caused controversy with their comments about the president recently.

Last month, comic Kathy Griffin suffered a huge backlash when a photo of her holding a severed head in the likeness of the former 'Apprentice' star appeared online.

She later said: ''I'm a comic, I cross the line, I move the line and then I cross it. I went way too far.... I made a mistake and I was wrong.''