"We are not leaving the SLFP we will still be in the party but we will work to 'save' it," Sooriyaarachchi told LBO.
"We will begin our work by making floral offerings at the Bandaranaike Samadhiya on Friday."
The 'Samadhiya' is the memorial of SLFP founder Solomon Bandaranaike, the father of former President Chandrika Kumaratunga, at the family's ancestral home in Horagalla.
Samaraweera was a close ally of Kumaratunga, but was sacked by President Mahinda Rajapakse, who is from the SLFP, along with Sooriyaarachchi and Anura Bandaranaike, Kumaratunga's brother earlier in the year.
Anura Bandaranaike rejoined the government.
In a letter to the Speaker, Samaraweera sought permission to make a 'private statement' in parliament on Wednesday, claiming that the ruling coalition has betrayed the