Premiership and Championship clubs have been told they can resume training on a non-contact, socially-distanced basis.
The top-flight season has been paused since 16 March because of coronavirus, but it is hoped the campaign can still be played to a conclusion.
All levels below the Premiership, including the Championship, have seen their seasons cancelled.
It has already been confirmed that Newcastle will be promoted.
The pandemic has meant no Premiership rugby has been played since 8 March, while Championship sides last played on 14 March.
“The clubs will need to satisfy a number of requirements to start stage one as we continue the huge amount of work being undertaken to enable a safe return to training,” said professional game board chairman Chris Booy.
“The welfare of the players, management and staff is our only priority and we look forward to the season resuming when it is safe to do so.”
Stage one training is non-contact and must be done in small groups, with each person at least two metres apart.
Premier League football clubs have since moved into stage two, which allows contact training in larger groups.
It is not known if, or when, rugby union clubs will be able to move to stage two or three, which is the resumption of matches behind closed doors.
Before players can return to training they must take an education module on Covid-19, while clubs will have to appoint both a Covid-19 manager and medical lead.
Clubs will also have to provide appropriate personal protective equipment, adhere to strict cleaning and hygiene standards and screen players and support staff on a daily basis for symptoms.