Trinamul Congress MP and East Midnapore heavyweight Sisir Adhikari, 79, joined the BJP on Sunday afternoon in the presence of Union home minister Amit Shah.

“The day he (son Suvendu Adhikari) joined, I also (virtually) joined (the BJP),” Sisir said.

The Contai South MP remains a Trinamul representative in the Lok Sabha and unlike son Suvendu, is yet to tender formal resignations as the legislator.

“I will remain in the posts that I hold. Let them (Trinamul) do what they can about it,” he said.

Sisir ddin’t accept a BJP flag on the dais.

Delivering a brief speech on stage, he said: “I have been in politics for over 60 years, but my family had never been disrespected like this.”

“This is a fight for our self-respect…. Only if the same government is both at the Centre and in the state can there be development. I repose my faith in Prime Minister Narendra Modi and Amit Shah,” he added.

After the rally, he attacked Trinamul and Mamata, calling the party a factory and her the proprietor.

“She does as she pleases. Once Suvendu wins in Nandigram, we will wipe Trinamul out of this district,” he said.

Asked, senior Trinamul leader Somen Mahapatra said Sisir Adhikari’s conduct was “unbecoming” of his stature.

“We are surprised as we did not expect such behaviour from a veteran.… To be fielding questions on behalf of an opposing party while he is still formally with us is unethical. The party will take steps,” he said.

Sisir Adhikari was first elected MLA from Contai South in 1982. His induction into Trinamul came in 1999, following which he was elected its MLA in 2001 and 2006, and MP in 2009, 2014 and 2019.

Shah’s comments on Sunday were confined to the ambit of the bhaipo (nephew) discourse, with the Union home minister repeatedly asserting that Modi would transform the state into “Sonar Bangla” in five years.

“Trinamul’s downfall is imminent, it is inevitable,” he said.