Nippon Broadcasting System Inc. on Thursday started buying 6.3 million of its own shares at a cost of 6,300 yen per share -- or a total of 40 billion yen -- via a public tender that will end June 15.

The step is aimed at providing its shareholders with opportunities to sell their holdings ahead of the company's July delisting, the company said.

The shares subject to the tender represent 19.2 percent of the AM radio station's outstanding shares, it said.

Fuji Television Network Inc., which battled for control of Nippon Broadcasting with Internet service provider Livedoor Co., has made the radio company a subsidiary.

Fuji TV has acquired Livedoor's wholly owned subsidiary, Livedoor Partners Co., which holds a 32.4 percent stake in NBS. The deal raised Fuji TV's stake in Nippon Broadcasting, including shares held by Livedoor Partners, to 68.9 percent.

NBS is expected to be removed from the second section of the Tokyo Stock Exchange in late July, as the company is certain to fall under the bourse's delisting criteria.

The TSE transferred Nippon Broadcasting to its supervision post Tuesday.