The British acting legend, who is promoting 'Logan,' the latest X-Men installment, described Brexit as a "calamitous mistake".
During a press conference at the Berlinale Festival, Stewart issued a grovelling apology to Europeans on behalf of the British public.
Patrick Stewart said he was embarassed and ashamed of his country
It is not the first time the British luvvie has attacked the referendum result, as he blamed the vote on a "misled electorate and lies".
Stewart, who campaigned for the Remain vote, told the press: "I want you to be absolutely clear that more than half the nation did not vote for breakfast, oh I mean, for Brexit."
The actor joked to the crowd: "If only because Brexit is harder to digest."
However, he then contiued his impromptu speech on Brexit, calling the vote "an embarrassment and shame".
Stewart descrbed Brexit as a "calamitous mistake"
It was and is a calamitous mistake and on behalf of those who voted to Remain I apologise to you
He added: "The vote only went the way it did because the nation was lied to.
"It was and is a calamitous mistake and on behalf of those who voted to Remain I apologise to you."
Later during the press conference, Stewart drew parallels between Logan, the Wolverine X-Men film, which premiered in Berlin last night, and modern political developements.
He said the resonance of the picture's themes had grown stronger during production.
The actor said: "We did not set out to make a political movie and yet there are references and echoes in this movie that could not have been anticipated but exist today. That is serendipity."
Hugh Jackman, the Australian star of the blockbuster, agreed with the film's political prescience REMOANERS: These people hate BREXIT! Mon, January 16, 2017
Remainers are finding it hard to accept Brexit.
Play slideshow AFP/Getty Images 1 of 14
Hugh Jackman, the Australian star of the blockbuster, agreed with the political prescience in the film.
He said that the film deals with xenophobia and borders, issues that dominant the political landscape today.
- Logan SHOCK: Wolverine Deadpool crossover in 2020? Hugh Jackman open
- Sir Ian McKellen slams Brexit: 'Everything good is related to Europe'
- Outrage as A-list celebs lecture Brits in open letter to STAY in EU