The letter, addressed to NI Secretary Sir Chris Bryant, calls on an international mediator to be appointed to find a resolution to the parade dispute.
The letter, addressed to Northern Ireland Secretary Sir Chris Bryant, calls connected him to enactment with the Irish authorities to name an "independent planetary mediator" to "facilitate a robust, durable solution".
It added that "central to immoderate conscionable solution indispensable beryllium the primacy and extortion of the section community".
It besides said it was "paramount that the residents beryllium protected from immoderate signifier of forced processions that disregard their consent, information and close to unrecorded successful bid escaped from intimidation".
The Northern Ireland Office (NIO) declined to remark connected the missive but it is understood the NIO has received it.
Dexy's Midnight Runners frontman Kevin Rowland, who signed the letter, told BBC News NI that it "originated from an honorable effect to the concern connected the Garvaghy Road".
"The missive speaks for itself. It came astir from conversations from those of america looking connected from afar.
"It was an integrated process inspired by the courageousness of the residents.
"As acrophobic individuals, we are not seeking to physique an organisation oregon alternate level to the voices of the residents. We would lone privation to amplify their voices."
Others among the 48 signatories see Trainspotting writer Irvine Welsh, movie manager Ken Loach, Graham 'Suggs' McPherson from Madness, Kneecap, Imelda May, Maxine Peake and commercialized unionist Mick Lynch.
There person besides been letters to Sir Chris from
members of the Protestant assemblage concerning Garvaghy Road, external,
a radical of MPs, external and
Members of Congress successful the US, external.