Washington DC - President Donald Trump lashed out Tuesday hours before Jimmy Kimmel's late-night talk show was due to be back on the air, insulting the host, and threatening to "test ABC" over the move.

Kimmel's show returned Tuesday night after a week-long hiatus following government pressure on broadcasters that critics said amounted to a chill on free speech.

However, two powerful companies that own dozens of ABC affiliates have said they will continue their boycott, giving viewers "other programming relevant to their respective markets."

Trump took to his Truth Social platform to insult Kimmel and accuse broadcaster ABC of "playing 99% positive Democrat GARBAGE."

The 79-year-old Republican added: "I think we're going to test ABC out on this. Let's see how we do. Last time I went after them, they gave me $16 million dollars."

ABC agreed in December to donate $15 million to Trump's eventual presidential library to settle a defamation suit instead of fighting it out in court.

A separate $16 million settlement was paid by CBS' parent company, Paramount Global, to settle a different lawsuit over an interview with former Vice President Kamala Harris.

All eyes were on Kimmel's popular opening monologue Tuesday night, as the audience expected the comedian to address his suspension, which came after comments he made in the wake of the killing of far-right Charlie Kirk.

"I don't want him to apologize as soon as he comes in," 18-year-old Paul Dorner told AFP as he waited for a seat in the show's audience. "I would love for him to just put up a fight and stand up for what he thinks."

Rogelio Nunez (38) said he had traveled from San Diego for the taping in the heart of Hollywood.

"We need to make sure that we're not being censored," he said. "So besides just coming for entertainment, I think it's important to protect our rights."

Kimmel, who frequently skewers Trump and his inner circle, raised the ire of conservatives last week when he said "the MAGA gang" was trying to exploit Kirk's college campus murder for their own political gain.

Federal Communications Commission (FCC) Chairman Brendan Carr appeared to threaten the licenses of ABC affiliates broadcasting the show unless they demanded Kimmel's removal – something Trump himself has frequently called for.

Two companies that own dozens of those affiliates – Nexstar and Sinclair – then announced they would be removing the show from their schedules, prompting Disney to suspend the show nationwide.

Sinclair – which last week demanded Kimmel apologize to Kirk's family and make a donation to his far-right group Turning Point USA – said Monday its affiliates would not be broadcasting the show when it resumed. On Tuesday, Nexstar followed suit.

"We made a decision last week to preempt 'Jimmy Kimmel Live!'... We stand by that decision pending assurance that all parties are committed to fostering an environment of respectful, constructive dialogue in the markets we serve," the company said.

Kimmel's abrupt disappearance from the airwaves sparked widespread fury, with opponents saying he had been targeted because he is critical of Trump.

Opponents saw it as the latest step in creeping government control of the constitutional right to free speech.

Some on the political right were also uneasy, including those who regularly count themselves as Trump allies, like conservative Senator Ted Cruz and broadcaster Tucker Carlson.

Trump often complains about negative coverage of him, going so far last week as to call it "illegal," and has sued several media organizations.

Disney's ABC has already settled a lawsuit filed by the president, pledging a multi-million dollar sum in a move that observers said appeared to be an attempt to get the often-vengeful 79-year-old off its back.

The company faced backlash after suspending Kimmel, with a rash of consumer cancellations and a wave of reproach from creators and Hollywood insiders over what many saw as a spineless response to government bullying.

By Monday, Disney had backtracked, saying the suspension had been an effort to "avoid further inflaming a tense situation at an emotional moment for our country" and calling Kimmel's comments "ill-timed and thus insensitive." But it said it was bringing the show back after days of "thoughtful conversations with Jimmy."

Kimmel on Tuesday posted a photo on Instagram of himself with late producer Norman Lear – who was known for his advocacy of free speech – with the caption: "Missing this guy today."