The Liberal Democratic Party approved a proposal Tuesday to stiffen a law limiting foreign ownership of Japanese TV and radio broadcasters, party officials said.

Two LDP committees in charge of telecommunications and broadcasting policy approved the proposal at their joint meeting, setting the stage for the amendment being sent to the current Diet session, the officials said.

The current radio law limits the combined stake held by foreigners and foreign firms in Japanese broadcasters to less than 20 percent in terms of voting rights.

The law, as with similar laws in France and the U.S., is designed to prevent the possibility of foreigners taking control of a domestic broadcaster to air information that could undermine the public good.

The revision calls for including Japanese firms in which foreigners or foreign firms hold stakes to the types of investors the law is designed to regulate.

Calls for the proposed revision have been gathering momentum in political and media circles since Feb. 8, when Internet services company Livedoor Co. suddenly acquired a 29.63 percent stake in Nippon Broadcasting System Inc. in premarket-hours trading, bringing its combined stake in NBS to 35 percent.

At that time, Lehman Brothers Inc. lent 80 billion yen to Livedoor by purchasing convertible bonds issued by Livedoor to get cash to acquire the radio firm's shares.

Lehman Brothers' effective stake in Livedoor was 22.54 percent as of March 17.

But if Lehman Brothers converts all the bonds into shares, it could obtain a 33 percent stake. Lehman's purchase of the convertible bonds alerted LDP lawmakers to the fact that foreigners or foreign firms could feasibly take control of a broadcaster through Japanese firms partially or fully owned by them.