The vexed issue of promotion and relegation is back on the agenda for Premiership clubs as discussions take place over the feasibility of ­expanding the league from 12 to 13.

There are 13 shareholders in Premiership Rugby, the current top tier of a dozen plus last year’s relegated side, London Irish, who have made a sound start to regaining their status in the top flight and lead the Championship by four points.

The topic has been debated ever since the dawn of professionalism and the advent of leagues over 20 years ago. However, it has acquired fresh focus as clubs consider their futures in the wake of approaches for investment from outside concerns such as CVC Capital Partners.

A scheduled shareholders meeting of Premier Rugby Ltd is due to take place next Tuesday, when the clubs will consider a £250 million offer for a stake in the league.

Telegraph Sport understands, though, that there has been no stipulation from CVC about ring-fencing the league as a prerequisite for investment. Investment talks are a separate issue.