The SLPP breakaway faction led by Nimal Lanza and Anura Yapa has met Samagi Jana Balawegaya chairman Sarath Fonseka and United Republican Party leader Patali Champika Ranawaka.
Both meetings took place at the parliamentary complex last week, where the upcoming elections were discussed at length.
A spokesman for the Lanza camp said they would reach an arrangement with SLFP leader Maithripala Sirisena as well.
However, no SLFP MP would be allowed individually into their fold, he stressed.
The Lanza faction intends to support incumbent Ranil Wickremesinghe at the next presidential polls.