Trump disavows his supporters "send her back" chanting

US President Donald Trump said Thursday he was "not happy" with the "send her back" chant that broke out at his re-election rally as he denigrated a Democratic Congresswoman he previously said should leave the US.

The chant came at a North Carolina rally on Wednesday as tensions escalate between the US President and four Congresswomen, informally known as The Squad.

"I was not happy with it - I disagree with it. But again, I didn't say that, they did," Trump said at the White House a day after his ardent supporters raised chants directed at Democratic congresswoman Ilhan Omar.

Somali-born Omar is one of the four non-white Democrat Congresswomen, whom Trump criticised in a series of alleged "racist tweets", chanting "send her back."