Toulon president Mourad Boudjellal has launched an audacious bid to see his three-time European champions join the Aviva Premiership.
A Premiership Rugby spokesman confirmed to Press Association Sport that a letter was received via email from the French club on Wednesday night.
Multi-millionaire comic book publisher Boudjellal's move looks highly unlikely to succeed, although the possibility of England's Premiership clubs discussing it should not be ruled out.
Boudjellal has had an ongoing and often bitter battle with organisers of the Top 14 -- France's premier domestic competition -- about matters such as the €10 million (£7.7m) salary cap, and most recently, new rules that were introduced last summer regarding player bonus payments now being part of the cap if they amount to more than 10 percent of a player's salary.
Toulon's expensively-assembled squad is packed with world stars like Bryan Habana, Matt Giteau, Ma'a Nonu, Leigh Halfpenny, Quade Cooper, Juan Martin Fernandez Lobbe and Duane Vermeulen.
And England World Cup winner Ben Kay believes Boudjellal's initiative might be aimed at "ruffling a few feathers" to get what he wants in France.
Outspoken Toulon chief Boudjellal told French newspaper L'Equipe that his club's Premiership presence would offer "a huge added value," adding: "I wrote for a contact. If this is not possible the next season, maybe the one after that.
"For them [the English], besides a big first, it would be a huge added value. And I'm serious in my approach."
A Premiership Rugby spokesman told Press Association Sport: "It is a bit early for us to make a formal response, but we will be doing so in due course. It does show the appeal of Premiership rugby."
England World Cup hero Jonny Wilkinson inspired Toulon to a first European title in 2013, with that trophy being retained the following season and in 2015.
Victory over Bath at the Recreation Ground on Saturday should secure a Champions Cup quarter-final place and keep Toulon on course for an unprecedented fourth successive European crown.
All cross-border competitions, though, require approval, which would mean involvement at some stage from the Rugby Football Union and French Rugby Federation if 55-year-old Boudjellal, who took control of Toulon in 2006, follows up his initial contact by pursuing a Premiership place.
The Premiership currently comprises 12 clubs, with an annual salary cap of £5.1m per club, plus two excluded players whose salaries sit outside the cap.
That base level figure rises to £6.5m next season, then £7m for 2017-18.
Kay, meanwhile, said: "Mourad Boudjellal is an interesting owner and he has made his frustrations with the French system known. He has also fallen out with all the other French owners. Perhaps it's more about ruffling a few feathers to get what he wants.
"But there was a time when Europe wasn't working well and the English teams were speaking to the French about starting their own competition.
"The Champions Cup has proven that Europe is still a fantastic tournament, and the more the big clubs play against each other the better, but I don't think this is a starter."