London Welsh chairman Bleddyn Phillips says the club would be open to quitting the English game to join the Pro12.
The Exiles have spent two of the last three seasons in the Premiership, during which time they have been based at Oxford's Kassam Stadium.
"It's a symbiotic relationship which could benefit all parties," Phillips told BBC London 94.9.
"I think it would bring an added dimension to Pro12 if you are able to establish a London franchise."
Following their relegation from the top flight last season, Welsh announced they will return to Old Deer Park in Richmond, their traditional home, for the 2015-16 season.
The Pro12, which began in 2001, currently features teams from Ireland, Scotland, Wales and Italy.
Phillips says the aspiration of London Welsh "has always been to play top-level rugby", adding: "We are a team that believes in its Welsh traditions and Welsh roots.
"As an option it [the Pro12] is attractive to many people in this part of London. It would be attractive to a number of Celtic teams.
"I suspect the likes of Munster, Ulster, Glasgow and Edinburgh would rather fly into Heathrow than to certain other areas which currently participate in the Pro12, while Welsh fans would prefer to come to south-west London than perhaps go further afield.
"There would be a degree of support behind the possibility."