Tom Smith was disappointed to miss out on a third Lions tour

The 33-year-old Northampton Saints player won 61 caps in an eight-year international career.

His final cap came in the 43-22 defeat by England in this year's Six Nations Championship at Twickenham.

Smith said: "It was a hard decision to make but one that I know is right for me and my family and it's definitely the right time to retire."

Smith's decision comes as no surprise, despite Matt Williams' removal from his role as national coach.

"I'm pleased with the changes which have been made recently but it's now time for me to focus on club rugby," added Smith.

"I wish the new management and all the players every success in the future."

He was the only Scot to start every Test of the last two Lions tours - to South Africa in 1997 and Australia in 2001 - earning plaudits for his performances along the way.

He captained Scotland throughout the 2001 autumn Test series and was awarded The Famous Grouse player of the season title for 2000-2001.

Interim Scotland manager Frank Hadden led the plaudits for Smith, saying: "You can't underestimate his contribution to Scottish rugby.

"He was the first outstanding ball-playing prop this country produced and he is a player with fantastic skill and a big heart.

"And he has brought great experience to the Scotland set-up from his times on tour with the Lions."