The 34-year-old flanker, who has won 77 caps and played in the past two World Cups, has struggled with ankle and toe problems with Northampton this season.

He joined Wasps in 2002 and spent seven years with the club before moving to Stade Francais, the Ricoh Black Rams in Japan and Super Rugby's Highlanders.

Haskell returned to Wasps in 2013 and moved to Saints last summer, but has only played four times this season.

"I have loved every minute of my career in rugby and feel very privileged to have played with and against some exceptional players," said Haskell, who also toured with the British and Irish Lions to New Zealand in 2017.

"This next chapter was supposed to go a very different way, however that is the nature of professional sport. I've never spent so much time injured in my entire career, but I'm doing everything I can to help the squad here until my contract ends.

"Retiring is obviously a really difficult decision for me to make; professional rugby has been the centre of my life for such a long time now and while it's weird to imagine living without it, I look to the future with huge excitement."

'One of the game's great characters'

Haskell is married to television presenter Chloe Madeley - the couple attended the wedding of Prince Harry and Meghan Markle last year and the pair blog about health and fitness

Haskell won three Six Nations titles with England and was part of the team that won the Grand Slam in 2016 before starring in the side that whitewashed Australia on tour that summer.

He played in England's 2011 World Cup quarter-final loss to France and was part of the Wasps side that won the 2007 Heineken Cup final.

England head coach Eddie Jones said: "It was a privilege to coach him, but also great fun. He's what I'd describe as a glue player - someone who always tries to bring a squad together.

"His tour to Australia in 2016 sticks in my mind. He was absolutely outstanding on that tour, amazingly physical, uncompromising and just totally dominant.

"Despite injuries preventing him from achieving his goals this season, he should be remembered for a great career and as someone who never gave less than 100% for club and country.

"Not only a superb player, but also one of the game's great characters; rugby will be poorer without the old fella."

Analysis

BBC rugby union correspondent Chris Jones

Haskell's dream was to bow out after a successful Rugby World Cup in Japan, but - as he acknowledges - sport doesn't always do fairytales.

Either way he can reflect on an outstanding career, where he not only achieved a huge amount on the pitch, but broadened his horizons off it.

And while as an international player he perhaps didn't have the consistency of say a Richard Hill, Haskell did produce some remarkable displays at the highest level.

His individual performances against Wales in Cardiff in 2015, and in Australia a year later, will go down in English rugby folklore.