The 22-year-old recently revealed he was considering the change and has now opted to make himself available to Craig Levein, who he played under while on loan at Dundee United two years ago.

Vale of Leven-born O'Brien, who played for Scotland Under-17 before representing Ireland at Under-19 and Under-21 level, told the Scottish Sun: "It's something I looked into and had a long think about.

"I have decided to make myself available for selection for Scotland in future.

"A chance came up to play for Ireland and I wanted to do that for my grandfather.

"But your situation changes and with Craig getting the job, I wanted to work with him again."

O'Brien, who is out of contract at Fir Park this summer and has been linked with a move to Aberdeen and Rangers, added: "I grew up watching Craig Brown take Scotland to the World Cup finals and if the chance comes along to win Scotland caps it would be great."