LONDON — Comcast said on Tuesday that it was making a $31 billion bid for the British satellite broadcaster Sky, potentially derailing 21st Century Fox’s efforts to acquire full control of the company.
Rupert Murdoch, the 21st Century Fox chairman, has tried for years to secure control of Sky but has found his efforts thwarted by a phone hacking scandal and concerns about allowing him to expand his already significant holdings in the British media market.
A British regulator provisionally rejected in January a bid by 21st Century Fox to take full control of the broadcaster by buying the 61 percent of Sky that it does not own. 21st Century Fox has offered a series of concessions to try to allay the concerns of regulators, including a promise to appoint an independent editorial board for Sky News.
At the same time, Mr. Murdoch agreed in December to sell the entertainment arm of his business, which would include the 39 percent stake in Sky, to the Walt Disney Company. 21st Century Fox is hoping to complete the Sky deal before the Disney sale is finalized.
“We think that Sky would be very valuable to us as we look to expand our presence internationally,” Brian L. Roberts, the Comcast chairman and chief executive, said in a statement.
“We believe that there are significant opportunities for growth by combining these businesses,” he added. “By combining the content, technology expertise and investment of Comcast with the market leading businesses and talent within Sky, we will create a very exciting platform for growth across Europe.”
Under the terms of its proposed bid, Comcast said it would pay 12.50 pounds, about $17.50, a share in cash, valuing all of Sky at £22 billion.
That would represent a premium of 13 percent to its closing price on Monday and is about 16 percent above 21st Century Fox’s current offer of £10.75.