Dayanidhi Maran, former Union minister and estranged grandnephew of Dravida Munnetra Kazhagam Chief M Karunanidhi, may abstain from the trust vote to be sought by Prime Minister Manmohan Singh in the Lok Sabha on July 22.
Sources close to the dissident DMK lawmaker told PTI that Dayanidhi was upset over the treatment meted out to him by the DMK leadership.
Karunanidhi had refused to meet him and his brother Kalanidhi Maran on his 84th birthday on June 3.
Dayanidhi Maran felt that DMK, for which he has 'done a lot', had treated him 'shabbily', they said.
Under these circumstances, he could not do anything but to abstain from the voting and if it happened, it would be only because of 'DMK leadership's mismanagement of MPs', the sources said.
"Did they treat me humanely? It should not be misconstrued that I am against Congress. I am not going to vote against the motion," Maran reportedly told his supporters on Tuesday.
The DMK leadership has already issued a whip to its party MPs to vote in favour of the trust vote.
Even as Maran, who was elected on a DMK ticket, mulled his stand on the motion, Karunanidhi on Tuesday launched the government-cable network, Arasu cable network to rival Maran brothers' Sumangali Cable TV vision, which controlled cable TV in Tamil Nadu.
Meanwhile DMK sources said if Maran abstains from voting, it not only amounted to defying the whip but also may attract disqualification.
Dayanidhi and Kalanidhi had fallen out of favour with Karunanidhi for the past one year after Dinakaran, the daily owned by them, published a survey, projecting the Tamil Nadu chief minister's son M K Stalin ahead of his brother M K Azhagiri in popularity.
Maran quit the Union Cabinet after the DMK asked the prime minister to drop him.