He said this in a post on his Instagram page on Friday.
He also disclosed that he had undergone successful surgery on Thursday and is already on his way to recovery.
The Englan midfielder confirmed that he will be supporting his teammates for the Europa League final as well as the Nations League from the sidelines.
He said, “Difficult to describe how I’m feeling right now. More confusion than sadness.
My surgery went very well yesterday evening 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 (Egland). 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”.
Chelsea play Arsenal in the final in Baku on Wednesday, 29 May.
England manager Gareth Southgate had earlier confirmed Loftus-Cheek would miss the final when announcing his squad for the forthcoming Nations League finals.
The player had been in the squad – but Southgate was forced to call up a replacement after learning of his injury.
“I went to bed last night and Ruben’s in the squad and playing brilliantly,” Southgate said.
“He misses now a major European final and a brilliant opportunity for us.”
He added it was a “huge disappointment” for the Chelsea man.
Loftus-Cheek scored in the second leg of the Blues’ Europa League semi-final against Eintracht Frankfurt and has been directly involved in nine goals in his past 15 competitive appearances for Chelsea.
Wednesday’s friendly raised £3.1m for organisations which combat hate crimes.
Ross Barkley scored twice either side of an Olivier Giroud header in the comfortable win in Foxborough.
Prior to the game, Chelsea manager Maurizio Sarri had expressed his concerns about travelling to the US so close to a major European final.