The 29-year-old’s future at the Hoops had been in doubt after he was handed a 12-game ban for his sending off at Manchester City on the final day of the Premier League campaign.
Barton had trained with Fleetwood Town during pre-season, sparking rumours of an unlikely move down to League Two.
But the QPR midfielder revealed his desire to join Ligue 1 outfit Marseille as the transfer deadline loomed and a loan deal was finally completed on Friday.
“My core driver to break from the Premier League is to fall in love with the game again, I said it when Fleetwood was on the cards,” said Barton.
“Reducing the ban was always complete nonsense from the media, Mark Hughes and I never saw it that way since I’d have to serve the ban somewhere and sometime, it’s not going anywhere unfortunately. It’s common sense.
“Moving to France and playing with a European giant like Marseille helps me realise this goal on a level that I couldn’t have imagined until now.”
He added: “I’m confident that I have a good 5-6 years in me yet, I’m fortunate that I have a great, natural engine and good people around me – so it’s all about being injury free and doing the business on the field.
“I want my remaining years in the game to be my best, I feel in my stomach that’s gonna be, too.”
Barton also thanked QPR for making his dream move become a reality, hinting he may still have a future at Loftus Road when his spell in France comes to an end.
“I’m grateful to the people the deal made this happen – let’s say that it had a few twists and turns. So thanks to my agent Willie Mckay, l’OM Sporting Director José Anigo and President Vincent Lebrune,” added Barton.
“I would also like to thank the QPR owners and executive management team Tony Fernandes and Amit Bhatia for supporting the move.”
He added: “Good luck to everyone at QPR for this season, they’ve made some great signings for the club – what would you expect of Mark Hughes backed by quality owners.
“Not least Mbia who was somebody that I initially looked forward to playing alongside at Marseille.
“Let’s not forget that I’m a contracted QPR player for two more years after this loan ends – who knows about my QPR future a year from now.”
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