LOS ANGELES — The Walt Disney Company was poised to complete a once-unthinkable deal to swallow most of Rupert Murdoch’s movie and television empire, a $60 billion-plus acquisition that would supercharge Disney’s global streaming-service ambitions, threaten to undercut Silicon Valley’s entertainment aspirations and most likely prompt further consolidation in Hollywood.

Disney was closing in Tuesday on an all-stock transaction to cleave out most of the assets of 21st Century Fox, which is controlled by the Murdoch family, with an agreement possibly coming as soon as Thursday, according to two people briefed on the matter, who spoke on the condition of anonymity because the talks — now down to the final details — were private.

“This is a massive, out-of-the-blue idea with enormous ramifications,” said Michael Nathanson, a longtime media analyst. “Direct-to-consumer services like Netflix will face more challenges for market share. For Hollywood, it begs for more consolidation. There will be one or two fewer studios a year from now. What happens to CBS and Viacom?”

Under the current contours of the discussions, which could always hit a last-minute snag, Disney would buy the 20th Century Fox movie and television studios; 22 regional cable networks dedicated to sports; Fox’s stake in the Hulu streaming service; cable networks like FX and National Geographic; and stakes in two behemoth overseas television-service providers, Sky of Britain and Star of India.