The versatile 34-year-old announced his decision on Monday, Football Federation Australia (FFA) confirmed in a statement.

Part of the 2015 Asian Cup-winning squad, Milligan also captained the Socceroos and his 80 caps are the equal eighth most in the nation's history.

"It has been a privilege to be involved with the Socceroos over the last 14-odd years. To be able to represent my country over that time is above and beyond anything I could have dreamed of," the Southend United man said.

"It hasn't always been smooth sailing – it was always going to be difficult to try and break into a squad full of Australian superstars. But I was given a chance, and just to be involved with players from Australia's 'golden generation' and learn my trade from them was an absolute gift that I will be forever grateful for.

"I was lucky to work under some wonderful coaches in my international career. Thank you to Guus Hiddink for first bringing me into the Socceroos' setup, and the late Pim Verbeek for keeping my dream alive. Thank you to Holger Osieck for handing me the captain's armband for the first time.

"A special thank you to Ange Postecoglou who showed great faith in me and gave me my first start at a World Cup, and a chance to play in the Asian Cup final. Ange taught me so much both in club and international football.

"Thank you to Bert van Marwijk and Mark van Bommel who put a lot of trust in me over the short time that they were in charge, and thank you to Graham Arnold who had a massive hand in me being called into the national setup way back when and named me captain over the last year. Being able to lead this team as captain over that time has been an absolute honour and something I will treasure forever.

"I wish the boys the best of luck going forward, knowing with Arnie in charge and a wonderful leadership group in place that the future is bright. There are exciting times ahead and I look forward to supporting the team along with the rest of the country."

Socceroos head coach Graham Arnold hailed Milligan's contribution in Australia colours.

"I am so proud of Mark and the career that he has had. Mark's commitment and desire for Australian football is up there with the best and I feel privileged to have been involved with him at the start and end of his international career," he said.

"Not many players can claim to have represented Australia at four World Cups, three Asian Cups, a Confederations Cup, as well as an Olympic Games. When you add in his tremendous club career, which includes two Hyundai A-League championships, a premiership, and a Joe Marston Medal, it is clear that Mark's contribution to Australian football over a long period has been significant."