The Tamil National Alliance (TNA) has announced its decision to support the UNP's no-confidence motion against Mahinda Rajapaksa in parliament, arguing that remainjng "neutral in such a situation, would pave the way for acheiving an undemocratic end by force."
The UNP brought the motion a week after President Sirisena sacked the UNP leader, Ranil Wickremesinghe as prime minister and appointed the former president, Mahinda Rajapaksa in his place.
In a statement the TNA said that at a meeting of its constituent parties it was decided that the president does not have the power to remove a prime minister who is in office and that such powers were repeated by the 19th Amendment to the constitution.
The president's decision to prorogue parliament is undemocratic, the statement added.
The TNA has also said it "strongly condemns and opposes the undemocratic efforts to use such delays to bribe Members of Parliament with both money and ministerial posts to induce them to cross over".
"We strongly condemn Tamil National Alliance Member of Parliament S Viyalendran being a part of this conspiracy. Necessary action will be taken against him immediately," the TNA added.