Robson, 74, is employed as a consultant by the Football Association of Ireland (FAI), having been appointed alongside manager Steve Staunton in January 2006.

Staunton left that job last month following Ireland's failure to qualify for Euro 2008 and Robson will stand down after Saturday's game in Wales, their final Group D qualifier.

"The day I signed I was a very fit, powerful man and had all my faculties," Robson told Sky Sports News. "I felt like Tarzan and I knew I could get on to the pitch. I could help Stan (Staunton) best by being on the pitch with the players but my health took a down turn.

"I found I had a small tumour on my brain that had to be removed and I became a little bit disabled so wasn't able to get on the pitch."

Robson has been treated for cancer on a number of occasions but has always returned to action.

He has spent 57 years in the game as player and coach in England, Spain, Portugal and the Netherlands and took England to the semi-finals of the 1990 World Cup.

His appointment with Ireland was intended to offer an experienced hand to Staunton, who was appointed with barely any international experience but the team failed to thrive.

"For the last two years I've enjoyed it and wish I could have done more," Robson said.

"Stan worked hard and did his best and I wanted to honor my contract and go to Cardiff for the last match."

Asked about his future plans, Robson said: "It depends on my health. I've still got my knowledge and enthusiasm but the chances are I'll never get back on to the pitch again."