Comcast (CMCSA) “is considering, and is in advanced stages of preparing, an offer for the business that Fox has agreed to sell Disney,” it said in a statement. “Any offer for Fox would be all-cash and at a premium to the value of the current all-share offer from Disney.”

The cable giant said that while no final decision has been made, work to finance the offer and preparation to file key regulatory statements is “well advanced.” A person familiar with the discussions said earlier this month that Comcast was mulling such a step. Comcast was talking to investment banks about obtaining bridge financing for the all-cash deal, the person said at the time.

Comcast is threatening to roil a plan by Disney to bolster its dominance in entertainment. Fox agreed in December to sell its film and TV studios, cable channels including FX and National Geographic and other assets to Burbank, California-based Disney in an all-stock deal, valued at roughly $52 billion. Comcast said at the time that it “never got the level of engagement needed to make a definitive offer.”

Cool Reception

Comcast investors gave a tepid reaction to the idea. The stock declined 2.1% to $31.82 in early trading on Tuesday. Even before the announcement, Comcast’s expansion plans have weighed on the shares, which are down 19% this year.

A bidding war would further complicate a global game of M&A chess among media giants. Philadelphia-based Comcast has already made a 22 billion pound ($30 billion) offer to acquire the 61% stake in European pay-TV group Sky Plc that Fox doesn’t already own. Fox and Disney also are interested in buying the business.

Comcast won approval on Monday from the U.K. government to move ahead with the offer for Sky.