Legendary Star Wars composer John Williams, 86, became ill while in London this week, and will be unable to conduct concerts there and in Vienna.

Williams had been scheduled to conduct the London Symphony in A Celebration of John Williams in Concert on Friday at London's Royal Albert Hall. On Wednesday, that venue tweeted out the news that he would be unable to attend.

"Unfortunately, owing to a last-minute illness, John Williams greatly regrets that he is no longer able to join us for this concert and will be replaced by his colleague and dear friend Dirk Brossé," the tweet read.

Unfortunately, owing to a last-minute illness, John Williams greatly regrets that he is no longer able to join us for this concert and will be replaced by his colleague and dear friend Dirk Brossé conducting the @londonsymphony. Full details here: https://t.co/F9zPv2D7oE — Royal Albert Hall (@RoyalAlbertHall) October 24, 2018

In an article on its site, the Royal Albert Hall went on to say that Williams had traveled to London for the concert before falling ill.

"He so wishes he could be with everyone, and the knowledge that 5,000 of his friends will be joining together to celebrate his music is a great comfort to him as he recovers," a statement from Williams' management said. "He wishes everyone a very joyous evening of music."

No specific details as to Williams' illness were given.

The Vienna Philharmonic Orchestra posted on its site on Wednesday that Williams has canceled two upcoming concerts with that group, scheduled for Nov. 3 and Nov. 4.

"It would have been a great pleasure for us to perform with Maestro Williams and we wish him a speedy recovery," the orchestra site notes.

Williams is an Oscar- and Grammy-winning musical legend who is famous not just for the iconic musical themes of the Star Wars films, but for the music of Indiana Jones, Jurassic Park, Harry Potter and other classic films.

In March, he told Los Angeles' KUSC radio that he will be done creating Star Wars music after Episode IX comes out in 2019.

"It will round out a series of nine," Williams said at the time. "That will be quite enough for me."

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