Nine Ireland players have been selected in the British and Irish Lions squad to tour Australia with Rory Best the most high-profile Irish name to miss out.

Brian O’Driscoll, Paul O’Connell, Jonathan Sexton, Cian Healy, Conor Murray, Rob Kearney, Tommy Bowe, Jamie Heaslip and Sean O’Brien were the nine named in the squad at this morning's announcement.

It has been confirmed that Sam Warburton of Wales will be the tour captain.

The squad contains 15 players from current Six Nations champions Wales, 10 from England, nine from Ireland and three from Scotland.

Best, Simon Zebo and Mike Ross are the Irish players who will be considered unlucky to have been left out. Leinster's Ian Madigan was also thought to have a chance of making it with a late surge but has also missed the cut.

Best is particularly unfortunate but a series of uncertain lineout-throwing performances appear to have cost the Ulsterman his chance with Richard Hibbard, Tom Youngs and Dylan Hartley claiming the three hooking places.

He could well make the squad at a later stage as the injury rate in his position tends towards the attritional.

England captain Chris Robshaw, Toulon out-half Jonny Wilkinson and Scotland back-rower Kelly Brown were also left out of the squad.

New Zealand-born Scotland wing Sean Maitland, a cousin of Australia out-half Quade Cooper, England prop Mako Vunipola and 2005 Lions tourist Matt Stevens were among those to earn selection in tight calls.

Saracens prop Stevens, who missed the 2009 tour while serving a two-year drugs ban, retired from England duty after the 2011 Rugby World Cup, but has been included as one of three tight-head options ahead of Ireland international Ross.

Much of Gatland's squad was as expected, spearheaded by O'Driscoll, who is on his fourth successive Lions tour, 2009 captain O'Connell and Wales prop Adam Jones.

But there are also opportunities for a new generation of Lions, players such as Wales trio George North, Alex Cuthbert and Justin Tipuric, England pair Manu Tuilagi and Owen Farrell and Ireland loosehead Healy.

Gatland's squad is split into 16 backs and 21 forwards. Four weeks from today the party will leave for Hong Kong where they open the 10-match tour against the Barbarians on 1 June.

The Lions then head to Australia with the first of three Tests against the Wallabies in Brisbane on 22 June.

Warburton admitted he had known about the news for some time, saying: "Warren gave me a call, it's been nine or 10 days since I found out and the biggest secret I've had to keep.

"It's unbelievable, an accolade very few people achieve and it's an unbelievable honour."

Gatland said: "In the last two or three years he's been the most successful captain in the northern hemisphere. I have a huge amount of respect for Sam, he's an absolute professional and he leads from the front."

Gatland admitted it had been tough to leave out some players.

"There was a robust debate about the squad and there were healthy discussions for every position," he said.

"Some real quality players have missed out. We had a thorough process and it's been tough."

He did offer hope to those left out, however, saying: "If you look at previous tours six to eight players get injured and there will be a group of back-up players who can be called upon."

37-man Lions squad to tour Australia: 

Backs: Leigh Halfpenny (Wales), Stuart Hogg (Scotland), Rob Kearney (Ireland); Tommy Bowe (Ireland), Alex Cuthbert (Wales), Sean Maitland (Scotland), George North (Wales); Jonathan Davies (Wales), Brian O'Driscoll (Ireland), Jamie Roberts (Wales), Manu Tuilagi (England); Owen Farrell (England), Jonny Sexton (Ireland); Conor Murray (Ireland), Mike Phillips (Wales), Ben Youngs (England)

Forwards: Dan Cole (England), Cian Healey (Ireland), Gethin Jenkins (Wales), Adam Jones, (Wales), Matt Stevens (England), Mako Vunipola (England); Dylan Hartley (England), Richard Hibbard (Wales), Tom Youngs (England); Ian Evans (Wales), Richie Gray (Scotland), Alun Wyn-Jones (Wales), Paul O'Connell (Ireland), Geoff Parling (England); Tom Croft (England), Toby Faletau (Wales), Jamie Heaslip (Ireland), Dan Lydiate (Wales), Sean O'Brien (Ireland), Justin Tipuric (Wales), Sam Warburton (Wales)