Ewan McGregor has refused to be interviewed by Piers Morgan because of the TV presenter's comments about the women's anti-Donald Trump marches.
The Trainspotting actor was due to appear on Good Morning Britain on Tuesday, but changed his mind when he learned Morgan was a host.
Morgan had previously voiced his disapproval at the protests, saying: "I'm planning a men's march to protest at the creeping global emasculation of my gender by rapid feminists. Who's with me?"
McGregor tweeted: "Was going on Good Morning Britain, didn't realise Piers Morgan was host.
"Won't go on with him after his comments about women's march."
Morgan hit back on Twitter and accused McGregor of throwing a "thespian tantrum".
He tweeted: "Sorry to hear that @mcgregor_ewan - you should be big enough to allow people different political opinions. You're just an actor after all.
"A real man would have come on and debated it with me, not run away like a coward.
"I'll be writing a column about @mcgregor_ewan today, once I have sent it to him for his approval."
He then tweeted simply: "Vainspotting."
More than five million people took part in protests across the globe on Saturday against the US President's agenda and rhetoric.
:: Millions of women protest against Trump worldwide
In the United States, organisers said one million demonstrators took part in the Women's March on Washington to express their concerns that women's rights will be eroded under the billionaire's presidency.
More than 600 "sister marches" were held in conjunction with the Washington event around the world - including in Sydney, London and other major US cities including Chicago, Atlanta and New York.
:: Madonna defends blow up White House 'metaphor' at Trump march
Among the famous faces in the crowds were actors Charlize Theron, Scarlett Johansson, Jake Gyllenhaal, Emma Watson, America Ferrera and Ashley Judd, as well as singers Madonna, Katy Perry and Cher.