The 39-year-old Essex-born swimmer has claimed six World Championship titles but never won an Olympic medal in five appearances having made his debut in the Games at Seoul in 1988, which are best remembered for Ben Johnson failing a drugs test after winning the 100 metres.

Foster, a national heart-throb after his appearance on the popular BBC show "Strictly Come Dancing", said that a comeback to swimming - with the London 2012 Games looming ever closer - is a definite possibility. 

He told insidethegames: "As it stands at the moment, I’m just taking things one day at a time.

"I haven’t said no [to a return to swimming] and I haven’t said yes.

"Who knows?

"We’ll just wait and see what happens but never say never."

Foster announced his retirement in 2006 only to return a year later when he won a silver medal in the 50 metres freestyle in the World Short Course Championships.

At the Olympics in Beijing last year he was chosen to carry Britain's flag at the opening ceremony.

But Foster failed to qualify for the men's 50m freestyle semi-finals, finishing almost two-tenths of a second outside the top 16 and then announced his retirement.

But he misses competing.

Foster said: "I'm always jealous [of those competing].

"When you’re a sportsman, you always want to be out there competing.

"You have to realise though, that your window eventually closes and that all good things can come to an end, especially in sport.

"You have to realise that you won’t be out there forever and I might not swim [competitively] again; but I might.

"The little kid in me wants to do another [Olympic Games] but he will always be there so I’ve got to shut him up eventually but no, I’m not ruling out anything."

If he does make a comeback and compete in London, Foster will be even older than the American Dara Torres (pictured), who was 41 when she swam in Beijing last year, her fifth Olympic appearance in a career stretching back to the Los Angeles Games in 1984.

Foster admitted that he has been inspired by the success of Britain's female swimmers.

He said: "You're always going to have peaks and troughs and you always going to have people coming through and that is what has happened in Britain.

"In the past, it’s predominantly been the men [in Britain who have had the most success] but right now, the women’s team is unbelievably strong.

"Girls like Becky Adlington are amazing and we need more role models like that in swimming so that people can look up to them and want to get into swimming because of them."

Foster believes that the London Olympics is a once-in-a-lifetime opportunity to encourage people to take up swimming.

He said: "London 2012 is all about inspiring people and getting people to participate in sport even if that’s just in moderation.

"If you are inspired and learn to swim because of it, that's fantastic because learning to swim can save your life for two reasons.

"You could obviously drown [if you haven’t have not learned to swim] and also from a health point of view, swimming can keep you fit and active and prevent disease caused from lack of physical activity."

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