President Donald Trump on Sunday once again unloaded on the four Democratic congresswomen known as "The Squad" after sparking considerable controversy last week by suggesting that they should "go back" where they came from, claiming that they should apologize to both the United States and Israel.

"I don't believe the four Congresswomen are capable of loving our Country. They should apologize to America (and Israel) for the horrible (hateful) things they have said," Trump wrote on his official Twitter account.

Last Sunday, Trump had fired off a series of tweets attacking the group of newly-elected lawmakers - all women of color and including Alexandria Ocasio-Cortez, African American Ayanna Pressley and Muslims Ilhan Omar and Rashida Tlaib.

As Trump said Sunday, these Democratic legislators, who have been sharply critical of the Republican president and his policies, "are destroying the Democrat Party."

They "are weak & insecure people who can never destroy our great Nation!" claimed Trump, once again upping his rhetoric against the four women.

In recent days, the president demanded that the congresswomen "go back" to where they came from, although three of them were, in fact, born in the US, precipitating an avalanche of accusations that Trump is a racist and white supremacist.

Ocasio-Cortez was born in the US and is of Puerto Rican descent, while Omar was born in Somalia and was brought to this country by her parents as a child, becoming a naturalized citizen years ago.

Tlaib is from Detroit and her parents are Palestinian, while Pressley was born in Chicago.

When asked about the matter, House Ways and Means Committee Chairman Elijah Cummings, a Democrat, said on Sunday that there was "no doubt" that Trump is a racist.

"What I'm hearing over and over again from my constituents is, please save our democracy," Cummings told ABC News on Sunday, adding "They say, 'I'm scared.' And I have never in my total of 37 years in public service ever heard a constituent say that they were scared of their leader."

On Friday, Trump called the members of his base "patriots" who two days before had chanted slogans of "Send her back!" - widely interpreted as racist - against Omar, thus negating his recent claim that he did not "agree" with those chants at a recent political rally where he was addressing that crowd in Greenville, North Carolina.

Despite the controversy surrounding the "Send her back!" chants, Trump on Friday doubled down on his criticism of Omar.

When White House reporters asked Trump if he regretted the Wednesday night chants, the president said: "Those are incredible people. They are incredible patriots. But I'm unhappy when a congresswoman goes and says, 'I'm going to be the president's nightmare.'"