Major TV networks - CBS Corp. (CBS), Fox, NBC, ABC, and the Spanish-language Telemundo -all have committed to continue transmitting in analog format until June 12, the new date when stations are required to broadcast only in digital format, Federal Communications Commission Acting Chairman Michael Copps said Thursday.

Congress has voted to postpone the digital TV transition date until June 12, and President Barack Obama is expected to sign the bill soon. But the legislation allows prepared TV stations to stop broadcasting in analog format before that date if they meet certain conditions and notify their viewers.

Once TV stations shut off their analog signals, viewers relying on over-the-air TV won't be able to watch their programs unless they buy a digital TV or converter box or subscribe to a satellite or cable TV service.

Gannett Co Inc. (GCI) and Hearst-Argyle Television Inc. (HTV) also have assured the commission that "a vast majority" of their stations will maintain an analog signal until June 12, Copps said.

ABC is owned by The Walt Disney Co. (DIS). NBC is a unit of General Electric Co. (GE). Fox is owned by News Corp. (NWS), which also owns Dow Jones Newswires.

Copps said TV stations that want to shut off their analog TV signals on Feb. 17, as originally planned, must notify the FCC by Feb. 9.

Obama officials, members of Congress, and consumer advocates pressed for a postponement of the original Feb. 17 digital transition date, arguing that the country wasn't ready for the shift. Some Republicans opposed the delay, noting the cost to broadcasters and confusion for consumers.

In deference to TV stations' preparation for a Feb. 17 digital shift, Congress gave broadcasters flexibility to shut down their analog broadcasts early. But Copps said the FCC is reserving the right to deny those requests "if we find it would not serve the public interest or if it would frustrate Congress's goal of giving consumers adequate time to prepare."

FCC Commissioner Robert McDowell noted that some stations may be forced to lay off staff if they incur the cost of maintaining an analog signal for several more months.

The commission will analyze their requests on a case-by-case basis.

-By Fawn Johnson, Dow Jones Newswires; 202-862-9263; fawn.johnson@dowjones.com