Comcast Corp (CMCSA) - Get Report is reportedly exploring financing for a bid to challenge Walt Disney Co.'s (DIS) - Get Report purchase of much of Twenty-First Century Fox Inc. (FOXA) - Get Report .

Shares of Comcast were down 0.1% at $32.35 after hours, following a report from Reuters that the Philadelphia media giant is preparing an all-cash offer. Fox jumped more than 5% to about $40 per share, while Disney fell 0.5% to $102 per share.

Fox agreed to sell most of its assets to Disney in December for $52.4 billion in equity, or about $66 billion including debt. Disney would buy Fox's film and TV studios and related assets; cable networks including FX Networks, Fox Sports Regional Networks; Fox's international networks; Indian satellite TV group Star India; and stakes in National Geographic Partners, Hulu LLC, UK satellite TV group Sky and other assets.

Rupert Murdoch reportedly had concerns about the regulatory outlook for sale of media assets to Comcast, which owns the largest U.S. cable operator. The Department of Justice sued in November to block the sale of Time Warner Inc. (TWX) to AT&T Inc. (T) - Get Report , which owns DirecTV, the largest U.S. pay-TV company. 

Comcast has already launched a bidding war with Fox for European satellite TV company Sky plc.

Comcast offered £12.50 per share for Sky in late February, topping a bid of £10.75 from Fox, which owns 39% of the U.K. satellite TV company.

A Comcast bid for Fox would be especially bold, considering that the Justice Department's lawsuit against the AT&T and Time Warner deal is undecided. The parties made closing arguments on April 30, and Judge Richard Leon said he will rule by June 12.

Comcast declined to comment.

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