A Direct TV dish is seen outside a home in the Queens borough of New York Thomson Reuters LOS ANGELES (Reuters) - DirecTV Chief Executive Officer Mike White on Thursday called for U.S. regulatory scrutiny of Comcast Corp's proposed purchase of Time Warner Cable Inc and the "effective broadband monopoly" he said it might create in as much as two-thirds of the United States.

White said his company, the nation's largest satellite TV provider, was still determining what position to take with Washington regulators who will review the merger. The deal will be reviewed by the Federal Communications Commission and either the U.S. Department of Justice or the Federal Trade Commission, the two agencies that share antitrust oversight in the United States.

"If the deal is approved as proposed, it clearly represents an unprecedented media concentration in one company," White told analysts on a conference call after DirecTV reported quarterly results.

"One of the challenges is to try and ensure that it is appropriately scrutinized," he said.

Comcast, when it announced the deal on February 13, said it would not reduce competition because the two cable providers do not compete in any markets. Comcast also said the deal would benefit consumers, in part because it would eventually result in higher broadband speeds.

A Comcast spokesman had no comment on White's remarks.

(Reporting by Lisa Richwine; Editing by Jan Paschal)