Mr Supriyo, a former BJP MP, was dropped from the Union ministry last year.
Trinamool Congress (TMC) MLA Babul Supriyo has been appointed as a national spokesperson of the party, sources in the Mamata Banerjee-led camp said.
Mr Supriyo, the former union minister, took to Twitter to thank the party supremo for giving him the new responsibility.
"My sincere gratitude to Hon'ble Didi @MamataOfficial & @abhishekaitc for appointing/including me in the illustrious Team of National Spokespersons of @AITCofficial. Shall do my very best to live up to the responsibility entrusted upon me," he tweeted.
A senior TMC leader said Mr Supriyo's appointment as a national spokesperson was a part of the strategy devised by the party to expand its base outside Bengal.
"He is a well-known face across the country, both as a singer and a politician. So he can help us place our views and policies on the national stage," the TMC leader said.
Mr Supriyo, a former BJP MP, was dropped from the Union ministry last year, following which he switched over to the TMC.
He gave up his Asansol Lok Sabha seat, which he had bagged on BJP tickets twice.
The singer-turned-politician was then nominated by the ruling TMC for the Ballygunge assembly bypoll in April this year, and he managed to clinch the seat by a comfortable margin.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)