The Adani Group is set to buy a majority stake in NDTV after indirectly acquiring 29.18% of the television channel, which the promoters of the company said was done without consent or notice.

Adani indirectly bought a 29.18% stake in New Delhi Television Ltd and said it will launch an open offer for another 26% stake. The open offer would be worth Indian Rs 493 crore ($61.73 million), according to a press release issued by the company.

The announcement came as a surprise to the founders of NDTV, veteran journalists Radhika Roy and Prannoy Roy, a statement by the media group said. The news channel has claimed that the 29.18% of NDTV has been acquired without "discussion, consent or notice".

The Adani group has business interests in Sri Lanka as well. The group was given the green light to commence the construction of two power plants in the country last week.