With St. Patrick's Day in full swing, celebrities have been taking to Twitter to express their love of the Irish!

Cheryl Cole was quick off the mark to send her St. Patrick's Day greeting saying:"Happy St. Patrick's Day #loveamerrypaddy [sic]"

Justin Timberlake used Twitter to share a classic YouTube video about a man in Alabama who claimed he was a Leprechaun. He finished off the tweet with "On this day every year, I can't help but think of this classic...Happy St. Patty's!!! [sic]"

Irish comedian Dara O'Briain also used the social networking site to post a greeting. "Happy St Patrick's day everyone. Beannachtaí na Feile Oraibh go Leir! [sic]"

Rory McIlroy expressed his hopes for an Irish win later today when they take on England in the Six Nations.

"Happy St Patricks day everyone!! Ireland beating England at Twickenham would make it just about perfect [sic]"

And as always Chris O'Dowd added a bit of humour with his tweet, saying: "Happy Anti-Snake day. Please RT this and stop the Spread of Snakes in Ireland [sic]"