Tom Wheeler, the head of the Federal Communications Commission, said Tuesday in Philadelphia that he "has not done enough" to bring competition to Comcast and other cable companies.

Speaking at the Wharton School at the University of Pennsylvania, Wheeler also said he hoped to open cable's lucrative set-top box business to outsiders so consumers will have more control over what they watch on TV.

"Everybody can get anything [on their TV], and a thousand flowers bloom," Wheeler said.

The cable industry collects about $20 billion a year from its captive set-top boxes, which control the signals coming into homes. The FCC recently released its plan that would enable others to develop set-top boxes, and the agency's five commissioners will vote on it later this month.

Wheeler answered questions Tuesday afternoon at Wharton. Responding to one, he said he did not visit Comcast headquarters and had walked directly to Penn from the train.

He added that he thought highly of Comcast executives. "We can have policy differences and not call each other cretins," he said.

Wheeler, 69, said he has known Brian Roberts, 56, since the Comcast CEO was a teenager. And Wheeler also knew his late father, Ralph. Wheeler served as president of the National Cable and Telecommunications Association, cable's lobbying organization, in the late 1970s and early 1980s. He also was a venture capitalist and a major Democratic fund-raiser.

He would not say what he disliked about Comcast's failed plan in 2015 to buy Time Warner cable, which the agency frowned on. But he also said the deal wouldn't add to competition where the firms would operate.

At the same time, the FCC green-lighted AT&T's bigger deal to buy DirecTV. The merged firm offers more competition to Comcast in many major markets with a so-called quad-play of phone, Internet, TV, and wireless services.

AT&T/DirecTV also surpassed Comcast as the nation's largest pay-TV operator, a mantle that Comcast held for more than a decade.

The FCC is now reviewing Charter Communications Inc.'s proposed deal to merge with Time Warner Cable Inc.

Wheeler has advocated for open Internet regulations opposed by Comcast and other Internet service providers. The FCC approved the open Internet, or "net neutrality," regulations in 2015. Telecom companies have sued to overturn the regulations.