Loftus-Cheek went under the knife on Thursday evening after rupturing his Achilles tendon in the first half of a 3-0 charity friendly victory over Major League Soccer outfit New England Revolution at Gillette Stadium in Foxborough, Massachusetts.
The 23-year-old England international will now miss the Europa League Final against Arsenal in Baku on May 29 in addition to the Uefa Nations League Finals.
"Difficult to describe how I'm feeling right now," Loftus-Cheek wrote on Instagram on Friday. "More confusion than sadness.
"My surgery went very well yesterday so I'm off to a good start.
"I'll be watching and supporting from the sidelines for a little while so I wish the boys all the luck in the Europa League final and of course the nations league finals.
"Coming back strong from an injury is something I've had to do all my life and I'll do it again.
"See you on the pitch as soon as possible."