Mayim Bialik, Helen Mirren, Scooter Braun, Selma Blair and more than 380 others also lent their names to open letter.
The 22-year-old singer is the first female artist to win the song contest in 10 years.
The petition's initiator reportedly referred to Israel violating human rights during the now-four month battle with Hamas militants following their Oct. 7 attack.
Sweden won the annual continental competition, sending the artist into the top 10 of the Global Excl. U.S. survey.
An estimated TV audience of 160 million watched the 67th edition of the contest, held in Liverpool, U.K., on behalf of war-torn Ukraine.
The song contest's audience of over 160 million last year shows its unrivaled reach as a marketing platform for record labels to develop artists.
Australia, Austria and Belgium among countries with popular acts joining favorites Sweden and Finland on Saturday night at Liverpool's M&S Bank Arena.
In U.K.’s first Eurovision hosting in 25 years, Liverpool stands in for 2022 winner Ukraine, which continues to fight a war with Russia.
This year's competition kicks off in Liverpool this week.
The event is taking place in Liverpool, with the U.K. hosting the event on behalf of Ukraine.