I don't know if there is one. I'd say the RCPB-ML in the 1970s-80s but I don't know about after that.
What group should workers in Britain join?
No, I'm not British and even if I were I wouldn't be in the CPGB-ML considering that they consider Hoxha to have been "ultra-left" and "sectarian," they uphold modern-day China as socialist, and other silliness.
Hello, are you in the CPGB-ML?