Directed by Liza Johnson, and starring Kevin Spacey as President Richard Nixon, the movie is a satirical comedy which imagines what might have happened behind closed doors at The White House during a real-life 1970 meeting between the two men, and Shannon admits his costume helped him get into character.

"I loved my costume: the wig, the belts were incredible," he told The Hollywood Reporter. "Just showing up to work every day and transforming."

However, the 41-year-old admits he felt rather out of his depth on the first day of shooting when he realised he had to play such an iconic American figure.

"Just diving into it and getting over the jitters (was tough)," he explained. "The first scene was in the Oval Office - we started with the climax of the movie because of Kevin’s schedule. But once I crossed that threshold, I had a pretty good time."

But despite the daunting prospect of portraying Elvis onscreen, and his ever-busy work schedule, Michael, who has appeared in two films on show at the 2016 Tribeca Film Festival in New York, admits he is living the Hollywood dream.

"I'm pretty much always working, so it’s hard to imagine wanting to do something else," he said. "(I have) no regrets; just keep moving forward."

Elvis & Nixon hits the U.S. and U.K. on Friday (22Apr16).

Meanwhile, Shannon is also making waves on Broadway, starring opposite Jessica Lange in the revival of Eugene O'Neill’s family drama Long Day's Journey Into Night.