Former US president Donald Trump postponed a controversial rally yesterday at which he was set to appear with a political candidate accused of sexually assaulting eight women - citing bad weather and the possibility of tornadoes.

The Republican leader had sparked anger in Nebraska where he was due to share the stage with 67-year-old gubernatorial candidate Charles Herbster, who has denied the allegations but faces a backlash from conservatives.

"Because of severe weather, including the possibility of 60 mph-plus wind, hailstorms, and maybe even tornadoes, I will not be coming to Nebraska tonight, but rather, weather permitting, will be there this Sunday night, May 1st," Mr Trump said in a statement.

"The most important thing is to keep you safe, and that cannot be done with such a terrible forecast."

He thanked Mr Herbster, ending the message: "See you on Sunday! But it wasn't immediately clear if the "special guest speaker" at Mr Trump's "Save America" rally at a race track near Omaha would still be on the bill if the event were to go ahead 48 hours late.

The Friday evening forecast for Omaha on read: "Thunderstorms possible after 8pm. Damaging winds, large hail and possibly a tornado with some storms."

Charles Herbster is an unwavering loyalist who attended Donald Trump's 2015 campaign launch

Mr Herbster has been mired in scandal since state senator Julie Slama told the Nebraska Examiner two weeks ago that he had reached up her skirt and groped her during an event in 2019.

Seven other women also came forward anonymously with misconduct accusations against the entrepreneur, whose fortune comes in part from selling bull semen.

Aides informed Mr Trump of the allegations earlier this month, according to Politico, but the Republican leader doubled down, pushing for Mr Herbster to fight back.

The agricultural executive has dismissed the scandal as a "smear campaign" similar to attempts to target Mr Trump, who has been accused of sexual misconduct himself by more than two dozen women.

"Charles will continue to fight to expose politically-motivated lies, to clear his good name, and to focus on the issues that he will tackle as the next governor of Nebraska," his spokeswoman Ellen Keast said in a statement.

Mr Trump, 75, has a long history of backing public figures accused of misconduct, including White House aide Rob Porter after he was fired over accusations of battering two of his ex-wives.

Others who have benefitted from his support include former Fox News star Bill O'Reilly, accused of sexual harassment, and Supreme Court Justice Brett Kavanaugh, who faced historic sexual assault allegations during his confirmation.

Among candidates for office, the list includes Roy Moore, 75, who denied multiple sexual misconduct accusations but did not dispute that he had dated teenagers over the age of consent.

'Basic human decency'

The race for the Republican nomination in Nebraska on 10 May is a three-way toss-up between Mr Herbster, multimillionaire pig farmer Jim Pillen and state senator Brett Lindstrom.

Mr Trump's October endorsement of Mr Herbster, a prolific donor, rankled much of the Republican establishment in the state that Mr Trump won by 20 points in 2020.

An unwavering loyalist who attended Mr Trump's 2015 campaign launch and the rally ahead of the 2021 US Capitol assault, Mr Herbster is vying to replace Pete Ricketts, the scion of a powerful Republican dynasty that owns the Chicago Cubs.

The outgoing governor, who tried to dissuade Mr Trump from anointing Mr Herbster, said on Monday the candidate should apologise to his accusers, quit the race and "seek help".

Frustration is mounting on the right over the endorsements, which often appear to have more to do with the candidates' fame than their conservative credentials.

Mr Trump's support of "Hillbilly Elegy" author J.D. Vance in Ohio and celebrity surgeon Mehmet Oz in Pennsylvania underscores his willingness to defy the establishment, often putting him at odds with his own side.

And while Mr Trump's popularity with the hardliners that make up his core support appears undiminished, his endorsements may not be the panacea they once were.

Mr Vance's popularity has surged, but Mr Oz still trails a former US Treasury official, and Georgia gubernatorial challenger David Perdue has gone from seven to 25 points behind since Mr Trump's endorsement in February.

"This is not a question of politics - it is an issue of character and basic human decency," Ms Slama's 12 female colleagues in Nebraska said in a joint statement.

"Charles Herbster's behavior is completely unacceptable for anyone, especially someone seeking a public office of authority and trust."