After AT&T Inc announced the divestment of parts of Warner Media's business and a merger with DISCA.US, Lightshed Partners analyst Rich Greenfield said the deal could have an adverse impact on Comcast Corp's NBCUniversal and ViacomCBS (VIAC.US), Zhitong Financial APP learned.

For the past six months, there has been speculation that NBCUniversal might merge with Warner Media, a subsidiary of AT&T Inc.

"I can't believe Comcast Corp CEO Brian Roberts allowed this to happen instead of trying to block the deal and buy Warner Media," Greenfield said in an interview.

Greenfield further pointed out that Comcast Corp or ViacomCBS may acquire small media companies such as Starz of Lionsgate (LGF.A.US) or Epix of MGM.

NBCUniversal,Greenfield believes that its streaming service Peacock needs to focus on the development of content, and the company should add SVOD (subscription Video on demand) service.

In response to AT&T,Greenfield, the merger may be the quickest way for the company to seek cash, and the deal seems to mean that the company acknowledges that its vertical integration measures have failed.

It is reported that AT&T Inc will merge Warner Media's high-end entertainment, sports and news businesses with Discovery Channel, and the current Discovery Channel CEO Zaslav will serve as the new company CEO. AT&T Inc will receive a total of $43 billion through a combination of cash, debt and some of the debt retained by Warner Media.