Comcast Takeover of NBC Is Delayed Until Next Year

10:00 p.m. | Updated The long-awaited completion of the takeover of NBC Universal by Comcast will have to wait until the new year.

The companies said Wednesday that full regulatory approval of the deal, under which Comcast would initially acquire 51 percent of NBC Universal from General Electric, would not be completed by the end of December, as Comcast executives had hoped.

The news is a setback for Comcast, which said all year that it expected the deal — announced in December 2009 — to close by the end of 2010.

The delays have to do with some lingering questions involving what concessions Comcast will be asked to accept in order to win acceptance by the Justice Department and the Federal Communications Commission. The F.C.C. is preparing to circulate its order for the deal, perhaps as early as Thursday. Representatives for both agencies declined to comment on Wednesday.

According to filings before the F.C.C., online video has been a focus of discussions with Comcast. Accordingly, the agency is likely to impose strong conditions on the deal that would affect the online video market. There have been no indications that the agencies would block the deal outright.

Jeffrey Zucker, the outgoing NBC Universal chief executive, said in a memo to staff members Wednesday that “we have made substantial progress this month with both the F.C.C. and the Department of Justice, and expect that we will get a ‘green light’ in January.”

Sena Fitzmaurice, a Comcast spokeswoman, concurred in a statement, which read, “We are appreciative of the hard work by the F.C.C. and D.O.J. staff and by our own transition teams, and look forward to completing the process early next year.”

The deal has come under serious scrutiny from critics who say consumers will be harmed by the combination of Comcast’s cable operation and NBC’s portfolio of channels. Some of those critics are on Capitol Hill.

Senator John D. Rockefeller, Democrat of West Virginia who is chairman of the Senate committee on commerce, science and transportation, wrote to the F.C.C. on Dec. 10 to convey his concerns that “a media merger of this size has the potential to leave consumers with lesser programming and higher rates.”

In a letter to the F.C.C. chairman, Julius Genachowski, Mr. Rockefeller singled out the nascent online video market as an area where Comcast could cause harm by favoring its own content.

Once regulatory approval is obtained, there are other complications for Comcast and NBC, some of which are tied to bookkeeping. “The official close of the transaction would happen shortly after government approval,” Mr. Zucker said in the memo. “Until then, of course, business continues as normal.”