The DMK Friday announced the temporary suspension of former union minister MK Alagiri in the "interests of the party".
The suspension comes ahead of the DMK's state conference in Tiruchirapalli next month.
DMK general secretary K Anbazhagan said Alagiri was creating confusion in the party ranks and criticising the disciplinary action taken against some colleagues for "anti-party activities".
He said the continuation of Alagiri in the party was not proper and would destroy discipline. So, he said, Alagiri had been "temporarily suspended".
"The members should accept this decision taken in the interests of the party and should stand united," Anbazhagan said.
Alagiri, son of DMK president M. Karunanidhi, is against his brother M.K. Stalin being elected to the party's top post.
On Jan 7, Karunanidhi warned Alagiri and others that the party would act against those who defy the official line.
He said such action could include removal from primary membership of the party.
In a recent interview, Alagiri, the south zone organising secretary of the DMK, had opposed an alliance with the DMDK in the Lok Sabha polls.
Alagiri's opposition came after Karunanidhi advocated the alliance. A miffed Karunanidhi had termed Alagiri's views regrettable and condemnable.
The DMK chief also said that decisions on electoral alliances were taken by the party's executive and general council or other relevant bodies.
In recent times, the DMK has taken action against Alagiri supporters in Madurai, considered a Alagiri stronghold.