It was joined by pro-Pierre MendÃ s-France clubs ( Union of Clubs for the Renewal of the Left led by Alain Savary ) and left-wing republican groups ( Union of Socialist Groups ad Clubs of Jean Poperen ) . It was joined by pro-Pierre MendÃ s-France clubs ( Union of Clubs for the Renewal of the Left led by Alain Savary ) and left-wing republican groups ( Union of Socialist Groups and Clubs of Jean Poperen ) .