More than 400 celebrities have signed a letter in support of Jimmy Kimmel

The letter, published by the American Civil Liberties Union, reads: "We the people must never accept government threats to our freedom of speech. Efforts by leaders to pressure artists, journalists, and companies with retaliation for their speech strike at the heart of what it means to live in a free country.

"Last week, Jimmy Kimmel was taken off the air after the government threatened a private company with retaliation, marking a dark moment for freedom of speech in our nation. In an attempt to silence its critics, our government has resorted to threatening the livelihoods of journalists, talk show hosts, artists, creatives, and entertainers across the board. This runs counter to the values our nation was built upon, and our Constitution guarantees.

"We know this moment is bigger than us and our industry."

The letter asserts that now is the time to "defend free speech".

It continues: "Regardless of our political affiliation, or whether we engage in politics or not, we all love our country. We also share the belief that our voices should never be silenced by those in power - because if it happens to one of us, it happens to all of us.

"This is the moment to defend free speech across our nation. We encourage all Americans to join us, along with the ACLU, in the fight to defend and preserve our constitutionally protected rights."

The TV talk-show was taken off the air after Jimmy suggested that Tyler Robinson, the man accused of fatally shooting Kirk at a university in Utah, was aligned to the Make America Great Again movement.

Jimmy said during a monologue on the show: "The MAGA gang desperately trying to characterise this kid who murdered Charlie Kirk as anything other than one of them and doing everything they can to score political points from it."

He added: "In between the finger-pointing, there was grieving."