The 26-year-old left Parisian giants Stade Francais at the end of last term and surprised the world by agreeing a short-term move to the Ricoh Black Rams.
He will now join up with the Highlanders early next year and will play a single season in New Zealand before heading home to rejoin London Wasps.
"I think it will help me in my desire to improve and become a better player for England," Haskell told The Times.
"The move to New Zealand and playing with and against some of the best players in the world in the country which holds the World Cup is another important step in that direction. That is the ultimate playing environment."
Haskell played five games at the recent World Cup but will miss the RBS 6 Nations and the summer tour of South Africa because of his Super Rugby commitments.
Ironically, Haskell will be based Dunedin, the city in which he became embroiled in controversy after an incident involving a female hotel worker during the pool stages of England's disappointing campaign.
The 42-times capped flanker cum No8 is one of five foreign players to agree deals with New Zealand sides next season and Highlanders coach Jamie Joseph believes he has the talent to make a big impact.
"James Haskell being available to play for the Highlanders is a bit of a coup," said Joseph.
"It's my job to pick the best players available in the world now, not just Otago. We have some quality loose forwards here already, but having the versatility of a player who can play internationally in all three loose forward positions is great.
"He's hungry to have a crack at Super Rugby, so we'll see how he goes."
Haskell will join fellow England international Danny Cipriani and Welsh cap Gareth Delve in the Super 15 just a season before the Lions head Down Under to face the Wallabies.