Mr. Trump holds rallies in Michigan and Wisconsin, two states vital to his 2016 win but now slipping away.

Donald Trump has verbally attacked Michigan's governor Gretchen Whitmer, despite warnings about the effect his words can have.

During a rally in the state, Mr Trump called on Ms Whitmer, a Democrat, to axe the remaining restrictions aimed at limiting the spread of the coronavirus.

He called her "dishonest" and joked about an extremist plot recently uncovered by the FBI to kidnap her, saying: "Hopefully you'll be sending her packing pretty soon".

His words prompted the crowd to chant: "Lock her up!"

Ms Whitmer wrote on Twitter: "This is exactly the rhetoric that has put me, my family, and other government officials' lives in danger while we try to save the lives of our fellow Americans."Advertisement

Earlier this month, 13 men were charged with plotting to overthrow and kidnap her from her holiday home, with one saying he wanted to try her for "treason".

Ms Whitmer's digital director, Tori Saylor, also urged the president to stop the dangerous words

She wrote on Twitter: "Every single time the president does this at a rally, the violent rhetoric towards (Ms Whitmer) immediately escalates on social media. It has to stop. It just has to."

Mr Trump did rallies in Michigan and Wisconsin on Saturday, two states that were vital to his 2016 win but now seem to be slipping away.

He told undecided and moderate voters that they had a "moral duty" to join the Republican Party, adding that the "Democrat Party you once knew doesn't exist".

He accused rival Joe Biden of wanting to "shut down the country, delay the vaccine and prolong the pandemic" - a pandemic that he tried to play down for a long time, despite warnings from public health experts.

He said a win for the Democrats would result in the "single biggest depression in the history of our country" and "turn Michigan into a refugee camp" but offered no evidence for his claims.

He also stoked fears that, even if he does lose November's election, he might not leave the White House gracefully, saying in Michigan that he "better damn well be president" in January.

Mr Trump moves to Nevada on Sunday, Arizona on Monday and Pennsylvania on Tuesday.

Despite Mr Biden leading the polls and having no public appearances scheduled on Saturday, his campaign manager warned against complacency.

Jen O'Malley Dillon wrote in a memo published by The Associated Press: "If we learned anything from 2016, it's that we cannot underestimate Donald Trump or his ability to claw his way back into contention in the final days of a campaign, through whatever smears or underhanded tactics he has at his disposal."