Before attending church on Sunday, Donald Trump defended a Fox News host who was taken off air after she questioned whether a Muslim congresswoman’s religious beliefs were compatible with the US constitution.

“Bring back [Judge Jeanine] Pirro,” the president tweeted from the White House, before a trip across Lafayette Square for a St Patrick’s Day service at St John’s Episcopal church. Fox should “be strong and prosper”, he added, rather than “be weak and die”.

Ilhan Omar, the subject of Pirro’s remarks, came to the US from Somalia and is one of the first Muslim women elected to Congress. Her remarks about Israeli influence on US politics have caused controversy on both sides of the aisle.

Pirro is an ardent supporter of the president on a channel with close links to the White House that are the subject of growing criticism.

On her show on Saturday 9 March, the former New York judge and district attorney said of the Minnesota representative: “Think about it. Omar wears a hijab, which, according to the Qur’an 33:59, tells women to cover so they won’t get molested.

“Is her adherence to this Islamic doctrine indicative of her adherence to sharia law, which in itself is antithetical to the United States constitution?”

Fox must stay strong and fight back with vigour. Stop working soooo hard on being politically correct Donald Trump

Amid outcry, Fox News said it “strongly condemned” the comments and had “addressed the matter with [Pirro] directly”.

In her own statement, Pirro said she had not called Omar “un-American” and said her intention had been to “ask a question and start a debate”.

“Of course because one is Muslim does not mean you don’t support the constitution,” she said, inviting Omar to appear on her show.

For her part, Omar thanked Fox and tweeted: “No one’s commitment to our constitution should be questioned because of their faith or country of birth.”

A week later, Pirro’s show did not appear. Citing an anonymous source, CNN reported that Pirro had been suspended but not fired. Fox repeated that it was “not commenting on internal scheduling matters”.

On Sunday, the president called for Pirro to be brought back and claimed “Radical Left Democrats working closely with their beloved partner, the Fake News Media” were working to “silence a majority of our country”.

“They have all out campaigns against Fox News hosts who are doing too well,” the president wrote. “Fox must stay strong and fight back with vigour. Stop working soooo hard on being politically correct, which will only bring you down, and continue to fight for our country. The losers all want what you have, don’t give it to them. Be strong [and] prosper, be weak [and] die! Stay true to the people that got you there.”

The president also defended the Fox host Tucker Carlson, who is under pressure over offensive comments made on talk radio beginning in the mid-2000s. Advertisers have said they will withdraw from his show and the show hosted by Pirro.

“Keep fighting for Tucker,” Trump wrote, “and fight hard for Judge Jeanine. Your competitors are jealous – they all want what you’ve got – NUMBER ONE. Don’t hand it to them on a silver platter. They can’t beat you, you can only beat yourselves!”

The tweets came after Trump’s repeated complaints about other TV shows: Saturday Night Live – which did not broadcast this weekend – and late-night talkshow hosts who mock him.

“Should Federal Election Commission and/or FCC look into this?” he asked. “There must be Collusion with the Democrats and, of course, Russia!”

He later criticised three Fox news anchors: Arthel Neville and Leland Vittert, who he said “should be working” for CNN, and “lowest rated anchor” Shepard Smith, a high-profile host who has been critical of Trump in the past.

In a more sensible forum, the Michigan Democrat Rashida Tlaib, another of the first Muslim women in Congress, appeared on CNN’s State of the Union.

“Congresswoman Omar and myself have gotten so many death threats,” she said, adding that she “actually prays every day for her safety”.

She added: “This is a woman that’s a mother, that is an American, that is serving her country. And we need to be very careful. When we disagree publicly, when we disagree publicly on various policy agreements, we have to be very careful in the language that we use … that it’s not feeding into the Islamophobia that is growing in our country.”