Boris Johnson appointed 16 new peers at Christmas taking the total to 52 in 2020 a move which raised the concern of Lord Speaker Norman Fowler.
Appointees included Scottish Tory MSP Ruth Davidson, Brexiteer former MEP Daniel Hannan, and Chair of Keir Starmer's leadership campaign Jennifer Chapman.
But critics say the Chamber is being stuffed with Tory and Labour donors and not accountable to the people, with peers entitled to a daily allowance of up to £323 outside normal Covid-19 pandemic times.
Tommy Sheppard, vice chairman of the Committee which was formed this week and SNP MP said: “The SNP welcomes the formation of a cross-party group to pursue electoral reform.