Tipperary South TD Seamus Healy has said his group is pulling out of the United Left Alliance in the Dáil.
He has said the Workers and Unemployed Action Group had decided to pull out of the ULA, citing frustration with its response to the revelations about Mick Wallace's tax affairs during the summer.
Mr Healy said a proposal that the ULA call for the Wexford TD's resignation from the Dáil had been blocked on separate occasions by the Socialist Party and the Socialist Workers Party.
The move is another blow for the Dáil Technical Group of Independent TDs, which has already seen North Dublin TD Clare Daly resign from the Socialist Party in the wake of the Mick Wallace controversy.
Deputy Healy also accused the Socialist Workers Party, represented in the Dáil by Richard Boyd Barrett, of being more interested in bolstering its own recruitment than in building a socialist alliance.