‘Don’t let it happen’: Trump says Kamala Harris cannot be first US woman president

Senator Kamala Harris "cannot" become the first US women president, Donald Trump told his supporters in Pennsylvania on Tuesday night, as he launched a fresh attack on the first black and Asian women to run on a major party ticket.

“But Kamala … Kamala by the way, she will not be your first woman president," Mr Trump, 74, told a jam-packed Make America Great Again rally at a dark and cold Erie International Airport.

"You cannot let that happen. There will be a woman president, you cannot let that happen," he added before going on to attack Democratic presidential nominee, Joe Biden and his running mate over both candidates' position on fracking.

With Joe Biden turning 78 next year, there have been murmurings on Capitol Hill that the former vice president might make way for his more youthful colleague after a few years in office, should he win November's election.

But Team Trump has claimed, without evidence, that senator Harris would be put in charge immediately after a Biden win, and installed as president soon after if Democrats control both Congress and the Senate.

Trailing his opponent in national and battlegrounds polls and desperate for a comeback, the president and GOP figures have repeatedly sought to frame the election as a choice between the president and senator Harris.

Over the past few weeks, Mr Trump has intensified his attacks on senator Harris, who was raised by a Jamaican father and an Indian mother.  

Those attacks have often been laced with sexist and racist undertones and aimed at winning back Republicans and independents who are comfortable with Mr Biden’s more moderate record, but may associate senator Harris with Democrats’ left flank, despite her own more centrist positions on some major issues such as crime.

The president described senator Harris as a "monster" and "communist" earlier this month following her clash with fellow VP candidate, Mike Pence during their first and only debate.

Back at his Pennsylvania on Tuesday night, the president essentially told the crowd he was only there because he was losing the race for the White House. He later cut the event short, in what was one of his most bizarre and incoherent performances to date.

Mr Trump has been hopping from one must-win stop on the electoral map to the next in the leadup to Thursday night's third and final presidential debate, when the two candidates will set out their competing visions for the country.

Meanwhile, Mr Biden has kept a low profile in recent days and was on Tuesday understood to be preparing for the final debate.