The Tamil National Alliance (TNA) is to decide next week on whether or not to support a no-confidence motion against the current Sri Lankan prime minister, Ranil Wickremesinghe.
Mr Sumanthiran was quoted by the Daily Mirror as saying the party's parliamentary group would meet on April 2 to discuss the issue and decide its position.
The no-confidence motion, reportedly signed by 55 MPs including a state minister and two deputy ministers, is to be debated in parliament on April 4.
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