A Democratic congressman who emigrated to the United States at the age of three called Donald Trump a 'racist a**' live on national television following the president's call for four minority lawmakers to go 'back where they came from.'

Representative Ted Lieu of California recalled his humble upbringing in an interview with MSNBC on Sunday before tearing into the president.

'As an immigrant myself, I know that when we came to America, we were poor,' Lieu recalled.

'My parents went to flee markets to sell gifts to make ends meet, and eventually they opened a successful small business and achieved the American dream. It’s one of the reasons I joined the Air Force and active duty.

'I never thought I’d see the day when a president was telling immigrants to go back to where they came from,' the congressman said. 'He’s demonstrating he’s a racist a**. He’s not uniting us.'

Rep Ted Lieu called Trump a 'racist a**' on live television following the president's comments

Born in Taipei, Taiwan, Lieu immigrated with his family to Cleveland, Ohio, in 1972.

He was first elected to Congress in 2014 and also serves in the United States Air Force Reserves, where he hold the rank of colonel.

He sits on the House Judiciary Committee, which is investigating Trump for possible obstruction of justice in the Russia investigation - a probe that began after Attorney General William Barr did not press charges against the president after special counsel Robert Mueller turned in his report.

Lieu's remarks went viral on Twitter.

'Had to moderate it for national TV,' the 50-year-old Democrat tweeted afterward.

'Not surprising that #RacistPresident is the #1 trending topic on Twitter,' he noted on Monday.

And he tweeted on Monday: 'Dear @realDonaldTrump: I'm an immigrant & served on active duty because I believe America is an exceptional country. What makes us great is that even though your skin color is different than mine, you are no more American than I am. And I will still be in Congress after you leave.'

George Conway, the husband of White House counselor Kellyanne Conway, retweeted the congressman's comments with the words: 'if the expletive fits.'

Trump, meanwhile, defended his tweets in which he suggested the four congresswomen, who are of racial minorities, go 'back where they came from.'

‘If you’re not happy here, then you can leave. As far as I’m concerned, if you hate our country, if you’re not happy here you can leave. That’s what I say all the time. That’s what I said in a tweet that I guess some people think is controversial. A lot of people love it, by the way. A lot of people love it. But if you’re not happy in the U.S., if you’re complaining all the time, very simply you can leave. You can leave right now. You can come back if you want, don’t come back, that’s ok, too,’ Trump told reporters on the South Lawn of the White House Monday afternoon.

Rep. Lieu attacked President Trump after his tweet critical of 'the squad'

Lieu came to the United States at age 3 and posted a Happy Mother's Day to his mom on instagram this year

Meanwhile, Nancy Pelosi announced Monday House Democrats are composing a resolution condemning President Trump's tweets against Alexandria Ocasio-Cortez and her 'squad.'

The speaker indicated there will be a vote soon in the chamber, a move designed to put Republicans on the record about their feelings on the president's tweets after few GOP lawmakers, thus far, have defended him.

No timing was indicated but Pelosi announced the forthcoming resolution in a letter to colleagues on Monday.

The president's twitter attack was seen as directed at Ocasio-Cortez, Ilhan Omar, Alyanna Pressley and Rashid Tlaib - four young, progressive lawmakers who took office in January after winning in the 2018 wave election that gave back control of the House of Representatives to Democrats.

They have dubbed themselves 'the squad.'

Trump was accused of a racist attack against the lawmakers, of whom only Omar was born overseas. She and her family fled war in Somalia and she is now a U.S. citizen. The rest of the lawmakers were born in the United States.

All have called for Trump's impeachment.

Omar and Tlaib are also the first Muslim women elected to Congress.

'Why don't they go back and help fix the totally broken and crime infested places from which they came,' Trump wrote on Twitter of ''Progressive' Democrat Congresswomen' on Sunday. 'Then come back and show us how it is done.'

'These places need your help badly, you can't leave fast enough. I'm sure that Nancy Pelosi would be very happy to quickly work out free travel arrangements!,' he added.