President Trump on Tuesday denied that his tweets suggesting that four minority congresswomen leave the country were racist, imploring House Republicans to reject a resolution that condemns his statements as “racist comments that have legitimised increased fear and hatred of new Americans and people of colour”.

On Monday, Trump told reporters he was not concerned that his comments about the so-called Squad were being heard as racist and embraced by white nationalists. A day later, the President raged on Twitter against the resolution, calling it a “con game”.

He renewed his harsh criticism of Representatives Alexandria Ocasio-Cortez of New York, Ilhan Omar of Minnesota, Ayanna S. Pressley of Massachusetts and Rashida Tlaib of Michigan.

“Those Tweets were NOT Racist,” Trump wrote. “I don’t have a Racist bone in my body! The so-called vote to be taken is a Democrat con game. Republicans should not show ‘weakness’ and fall into their trap.”

The vote on the resolution is developing into a show of unity for Democrats who had been squabbling for weeks — and a test of Republican principles.

In a closed-door meeting of House Democrats on Tuesday morning, Speaker Nancy Pelosi of California called the four freshman congresswomen “our sisters”, and said the insults to which Trump subjected them echo hurtful and offensive remarks he makes every day.

“So this is a resolution based in who we are as a people, as well as a recognition of the unacceptability of what his goals were,” Pelosi told Democrats, according to an aide present for the private meeting who described her remarks on condition of anonymity.

“This is, I hope, one where we will get Republican support. If they can’t support condemning the words of the President, well, that’s a message in and of itself.”

A smattering of Republicans have denounced the President’s performance, including Massachusetts governor Charlie Baker. Trump’s comments “were shameful, they were racist,” he told WBUR in Boston, “and they bring a tremendous amount of, sort of, disgrace to public policy and public life and I condemn them all.”

But Representative Kevin McCarthy of California, the House Republican leader and a close ally of the President’s, said he would oppose the resolution, and when asked whether Trump’s tweets were racist, replied flatly, “No”.

That drew an appreciative response from a President who appeared to be searching for validation for his statements.

Earlier, Trump attempted to shift the focus to what he called “HORRIBLE” things said by the four liberal freshmen congresswomen, who have been among the most outspoken in their party in their criticisms of him, including at a news conference on Monday where they described Trump as racist, xenophobic, misogynistic and criminal.

“This should be a vote on the filthy language, statements and lies told by the Democrat Congresswomen, who I truly believe, based on their actions, hate our Country,” Trump wrote. His latest broadside against the women comes hours before the House is poised to vote on a resolution that responds directly to his nativist tweets.