The saffron camp is focused to keep the pace that the party gained in the 2018 civic polls from the region for more gains against the ruling Trinamool Congress in the backward zone of West Bengal.
Replying to a question, he said he does not have any differences with the BJP's state president Dilip Ghosh.
The BJP at present has 15 MLAs in the Bengal House, including defectors. The Lok Sabha elections in 2019 threw up a surprise, as the party managed to wrest 18 seats.
Roy decided to set up an office in Salt Lake city from where he will chalk out his "game plan" aiming crucial 2021 Assembly elections in West Bengal, sources in the BJP said.
A number of BJP leaders including Roy and current party Lok Sabha member from Ranaghat Jagannath Sarkar have been named in the FIR related to Biswas' murder.
The bench also asked Roy to surrender before the trial court within four weeks to secure regular bail, besides submitting two sureties of Rs 50,000 each.
A division bench comprising justices Joymalya Bagchi and Suvra Ghosh, while dismissing the anticipatory bail prayer of Roy owing to a defect in it, gave him liberty to file a petition afresh.
The one time second-in-command of Trinamool, Roy's name figures in both the Saradha ponzi scam and Narada sting cases.
TMC founder member Mukul Roy's induction into the BJP evoked mixed reactions among the political parties in West Bengal.
BJP national general secretary Arun Singh today claimed that the Trinamool Congress was in "complete disarray" since Mukul Roy decided to quit.