The Sri Lanka Freedom Party (SLFP) has decided to back the no-confidence motion against Speaker Mahinda Yapa Abeywardena.
Opposition political parties had this week signed a no-confidence motion against Speaker Mahinda Yapa Abeywardena.
Leader of the Opposition Sajith Premadasa said the no-confidence motion is to be submitted to Parliament accusing the Speaker of unlawfully authorising the Online Safety Bill.
The Bill was found to be inconsistent with the Constitution by the Supreme Court, yet it was passed by Parliament and endorsed by the Speaker.
Alliance members in the Samagi Jana Balawegaya and the Tamil National Alliance (TNA) signed the no-confidence motion.
The National Peoples Power and independent groups in Parliament have also said they will support the no-confidence motion.