Taoiseach Leo Varadkar's partner Matthew Barrett has "unreservedly" apologized after his comments on social media during the coronation of King Charles III were described as "embarrassing" and "highly insulting."

"On reflection, poor judgment on my part," Barrett said in a tweet on Monday, May 15. "Unreservedly apologise for any offence caused."

On reflection, poor judgment on my part. Unreservedly apologise for any offence caused. https://t.co/XRegskoLjx

— Matthew Barrett (@GaothSaileDoc) May 15, 2023

According to The Irish Times, Barrett posted on his private Instagram account, which has about 350 followers, while attending the coronation with the Taoiseach at Westminster on Saturday, May 6.

“Holy s--t I think I’m accidentally crowned king of England,” he joked in one post featuring a photo taken from the Taoiseach’s car in the VIP motorcade as it headed along the Mall.

Inside Westminster Abbey, Barrett reportedly made quips based on the Order of Service, which said in part: "The queen’s scepter and rod are brought from the altar by the Right Rev and Right Hon the Lord Chartres GCVO and the Right Rev Rose Hudson Wilkin CD MBE, Bishop of Dover. The queen touches them in turn."

Barrett commented: "Sounds like the script to a good night out, tbh [to be honest.]"

He also commented on the title bestowed to the Right Rev James Newcome, who had the title Clerk of the Closet. 

"Clerk of the Closet? Had this job until my early 20s."  

Alongside an image of Charles being crowned, Barrett wrote: "Was genuinely half expecting it to shout ‘GRYFFINDOR.'"

Barrett's private Instagram posts were deemed "strange behaviour" by Miriam Lord in The Irish Times.

Elsewhere, Irish designer Paul Costelloe, who lives in London, described Barrett's behavior as “unbelievable carry-on."

"It will probably appear in the English papers. It’s really terrible,” Costelloe told The Sunday Independent.

“For people living over here, it puts you in a very embarrassing situation. I think it’s terribly hard to make excuses for that sort of behaviour.

"You can say it’s amusing and all, but you can’t do that type of thing. You have to be so careful over here. There is still this ‘Irish-English’ thing and they love finding something.

“Now they have got material to say look how we [the Irish] don’t know how to behave in such circumstances. We are back to the ditches and the fields. It’s highly insulting.

"You can say it’s amusing but it’s just terrible. It’s bad behaviour, it’s out of order and it’s a shame that something like this has happened when the [British-Irish] relationship has come so far.

"Obviously, Matthew thought it was a great joke.”

Earlier on Monday, ahead of Barrett's apology, Varadkar said in Co Limerick that his partner "of over seven years now" is a "private individual."

Varadkar said: "They were private messages sent on his private account, he never intended them to go public, but that happens sometimes.

"We've spoken about it and I think it's fair to say it won't happen again."