X-Men actors Sir Ian McKellen and Sir Patrick Stewart have shared a passionate kiss – at the premiere of McKellen’s latest film.

The pair caused a stir while appearing at the première of Mr Holmes, which features the veteran actor and gay rights campaigner as an elderly Sherlock Holmes.

Sir Ian was accompanied to the event at the Odeon cinema in Kensington by his close friend and X-Men colleague Sir Patrick, who is straight.

Posing for the cameras, the pair joked around – before sending the assembled media into a frenzy by sharing a smooch.

It appeared to be the pair’s reply to criticism of Stewart – who took to Facebook to defend himself from claims of homophobia after siding with a Christian bakery that refused to make a ‘support gay marriage’ cake.

Appearing on Newsnight, the actor he was “on the side of the bakers” and “supports their rights to say no”.

However, he took to Facebook to write: “I know many disagree with my sentiments, including the courts. I respect and understand their position, especially in this important climate where the tides of prejudices and inequality are (thankfully) turning.

“What I cannot respect is that some have conflated my position on this single matter to assume I’m anti-equality or that I share the personal beliefs of the bakers. Nothing, absolutely nothing, could be further from the truth.

“I have long championed the rights of the LGBT community, because equality should not only be, as the people of Ireland powerfully showed the world, universally embraced, but treasured.”

Judging by the kiss, it did not appear to have upset Sir Ian McKellen, who co-founded rights group Stonewall.

Stewart previously said he is “flattered” that people think he is gay.