IT was a clear-cut case of the pot calling the kettle black.

After Alex Salmond wore a pair of green and blue tartan trews to the Hollywood premiere of the animated film Brave, the former first minister Jack McConnell took to the social media site Twitter to poke fun at his rival's dodgy dress sense.

But the Labour grandee, now known as Baron McConnell of Glenscorrodale, was quickly reminded of his own fashion faux pas when he wore a modern pin-striped black kilt to an event at Tartan Week in the US.

Lord McConnell retweeted several messages from followers on Twitter saying Mr Salmond looked like a "hotel concierge" and "appeared to be wearing Donald's troosers".

He also posted a message from Labour researcher Michael Shanks saying the First Minister's outfit was worse than Lord McConnell's own fashion blunder from 2004, which was much derided as looking like a skirt.

Lord McConnell has since said photographs of him in the black kilt, which didn't have a sporran and looked slightly too small, have "haunted him" ever since, after some commentators dubbed it the "fashion crime" of the year.

One Holyrood insider yesterday said he was surprised that Lord McConnell had the brass neck to make fun of another First Minister's outfit.

He said: "For Jack McConnell to take the mickey out of Alex Salmond over a fashion faux pas is surely the pot calling the kettle black.

"What is it with our First Ministers that they can't attend a celebrity event without making themselves look completely ridiculous?"

Tessa Hartmann, chairwoman of the Scottish Fashion Awards, said she was less than impressed by Mr Salmond's outfit.

She added: "Now I understand why Alex Salmond has never graced the red carpet at the Scottish Fashion Awards, despite our yearly invitations to him.

"The fashion police would have decked and cuffed him there and then. You've got to hand it to him though – he is 'Brave' for wearing that outfit –the jacket looks like it's going to burst, perhaps he was trying to be in character? I would be happy to recommend a good Scottish tailor."

Lord McConnell posted the jokes in quick succession on Tuesday afternoon.

The first read: "At best the FM has pulled off the look of a man providing tours round a castle... at worst a hotel consierge![sic]" Another read: "BREAKING: Donald's troosers have been found, at a film premiere, in LA, on Alex Salmond." He also retweeted a post on his page from "Shanks" saying: "Surely this is much, much worse than @lordmcconnell's famous 'kilt' moment?"

An SNP spokeswoman was also quick to remind Lord McConnell of the skeleton in his fashion cupboard.

She said: "The First Minister was delighted to attend the premiere of Brave, a fantastic film which will secure many more visitors for Scotland – and the tartan trews got a big thumbs-up on the green carpet, and a cheer from the audience on the Craig Ferguson Show.

"They obviously don't have Lord McConnell's hang-ups, or his dismissive attitude to castle guides and hotel staff who do a great job for Scotland's tourism industry all year round. Jack has spent too long wrapped up in ermine in the House of Lords.

"Mr Salmond's choice of attire has been described as 'fetching' – in stark contrast to the former first minister's disastrous 'skirt moment' in New York."

Lord McConnell's infamous kilt was eventually sold for charity, raising £10,000.

He later admitted: "The photograph has come to haunt me. On the night, I think everybody who was there thought it was all part of this weird and wonderful display of outfits that people were wearing. Nobody who was there on the night has ever criticised it."