However, the TMC refused to give much importance to Singh's switch-over and challenged him to seek a re-election from his Assembly seat Bhatpara in North 24 Parganas district on a BJP ticket.
"I gave 30 years to Mamata Banerjee. I was shocked at her comments on the Pulwama terror attack. Her statement has shaken the country.
"When the Indian Air Force carried out the strike, she demanded the body count of terrorists. If a leader does not have national interest in her mind then she cannot do any good to her voters," Singh said.
Singh is likely to contest the Lok Sabha polls from the Barrackpore seat against TMC heavyweight and former railway minister Dinesh Trivedi, sources said.
He was upset with Banerjee for not giving him a ticket from the seat, they said.
"Earlier the TMC used to stand for Maa, Mati, Manush, now it is only money, money and money," Singh said in a brazen attack on Banerjee.
"Arjun Singh has been in touch with BJP leaders for quite some time. It hardly matters whether or not he is with us. What matters in the TMC is Mamata Banerjee," TMC's North 24 Parganas district president Jyotipriyo Mullick told PTI.
"If he has guts, he should resign and seek re-election from his Bhatpara Assembly seat. I can assure you, he will lose his deposits," he said.
The Bhatpara Assembly seat falls under the Barrackpore Lok Sabha constituency, which is currently held by Trivedi.
Mullick this evening held a meeting with TMC councillors of the Bhatpara Municipality, presently chaired by Singh, to ensure that they do not switch-over to the BJP.
Singh was at loggerheads with Trivedi, a two-time MP from Barrackpore. He had even told Banerjee that renominating Trivedi from Barrackpore would affect the party's prospects in the election. But the Trinamool Congress chief went ahead and re-nominated Trivedi.
Singh had expressed his anger against the TMC while speaking to reporters on Wednesday.
Singh, once considered to be close to former CPI(M) MP from Barrackpore Tarit Baran Topdar, has been game-changer for the TMC in several elections, from panchayat polls to parliamentary battles, due to his local connections and strong booth management skills.
Singh has influence over several Assembly seats in the North 24 Parganas district, which has a significant number of Hindi-speaking voters.
Reacting to Singh's defection, Trivedi said it will not have any impact as he is confident of winning the elections for the third time.
"It was the TMC which started this dirty game of poaching opposition MLAs in Bengal. Now, history is repeating itself. I would call it poetic justice," he said.
A total of 17 MLAs of the Congress and three of the Left Front had switched-over to the TMC since the 2016 state polls.
"There is no difference in the brand of politics both the parties practice," Mishra said.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)