According to The Sun, the Beady Eye frontman picked a fight with Elba while attending a bash at London's Ivy Club - poking fun at the Wire star's bobble hat.
An onlooker told the tabloid: "Liam was in full rock'n'roll swagger mode. He bowled up to the party after midnight and made his presence felt pretty quickly.
"He had a row with a Scottish actor called Martin Compston, mocking his accent."
They continued: "Then he had a few words with Idris, poking fun at his bobble hat among other things. Idris looked like he was going to flatten him - they were on completely different wavelengths.
"They were toe-to-toe at one point. Neither of them backed down. Idris was in a good mood, so left it, which was probably for the best. Liam left soon after."
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