Sir Ian McKellen said Pride events have always had the power to make LGBT+ people "feel a little better", even at times of oppression in which rights have been denied.
The 83-year-old acting legend marked 50 years of Pride in an interview with Metro, in which he reflected on how the celebration has changed over the course of five decades.
McKellen came out in 1988 and subsequently campaigned against the introduction of Section 28 legislation, which banned "the promotion of homosexuality".
For him, Pride is still connected with the politics of speaking out against those who seek to erode the rights of the LBGT+ community, as much as it's about partying and celebration.
Watch: Ian McKellen speaks out against Section 28 in 1988 interview
He said: "At its crudest, Pride is walking past Downing Street and blowing whistles at Mrs Thatcher. It doesn’t get you very far but it makes you feel a little better.
"Politics is about making connections and friends and Pride is the gay day and if that leads to a party, terrific."
The Lord of the Rings star said Pride serves a vital role in fostering a sense of community among people who may feel isolated due to what makes them different.
He said: "I think for most people, it was confirmation that what seemed like a personal problem you’ve been landed with by fate, was actually something that you could share with people who you would otherwise not meet."
McKellen acknowledged that his own experience as a gay man in the 1980s was not as tough as it was for others, with his sexuality well-known among other actors and those in the theatre community.
"I wasn’t unhappy as a young gay man, even though I was as closeted as all my friends, but I did have friends, gay friends," said the actor.
He added: "I lived openly with my partners. I wasn’t anywhere near as repressed as others, but I think I would have liked to have been told that it was important to me and important to others that I should care more about being gay."
McKellen continues to be a prominent activist for LGBT+ rights and also helped to found the charity Stonewall.
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