London Welsh chairman Bleddyn Phillips claims the club has received promises of financial support and stadium offers in their quest for Aviva Premiership status next season.
The Exiles' appeal against a decision barring them promotion to the Premiership is set to be heard in London on June 21.
The Exiles won this season's Championship after beating Cornish Pirates in both legs of the final.
But the Richmond-based club were told just hours before the first leg kicked off in Cornwall they did not meet minimum standards criteria set down by English rugby's Professional Game Board for Premiership entry.
London Welsh played the final's second leg at the Kassam Stadium in Oxford, their preferred venue should they gain top-flight status.
As things stand, Newcastle will remain in the Premiership next term despite finishing bottom by a point behind Wasps this season.
But should London Welsh succeed in overturning an original decision that went against them, then they will go up and the Falcons be relegated.
Phillips said that the club had received "overwhelming" support during recent days in its attempt to secure Premiership status.
"This includes not only the general rugby supporting public, but more specifically owners and managers of Premiership clubs and other rugby clubs, as well as leaders of clubs in the Football League and other sporting institutions," he said.
"These offers of help and encouragement extend not only to promises of financial and professional support, but also to offering up, in several cases, sporting venues as stadia where London Welsh might wish to play their 'home' games in 2012/13.
"We are most grateful for this, which to our mind underscores very sharply what we believe to be the fundamental issue at stake here.
"Namely, that any team which demonstrates on the field of play that it has the requisite skills and resources to win through to the top of its division or playing group should be allowed to move on to the next tier, thereby upholding the competitive spirit of sport in general and the ethos of promotion and relegation on merit-based principles.
"London Welsh, in common with other teams already based in the Premiership who ground-share with teams from the Football League, has arrangements already in place to play its 'home' games next season at a top sporting venue.
"It would rank, in our view, as one of the best grounds offering up Premiership rugby in 2012/13, and to our mind makes our case for promotion even more compelling and the reasoning behind its rejection even more difficult to fathom."