Donald Trump suggested delaying November's election in a highly controversial tweet on Thursday. Getty

A number of high-ranking Democratic politicians have condemned President Donald Trump's suggestions that November's general election should be delayed due to the threat of mail-in-voter fraud. 

Trump made the claim on his personal Twitter account on Thursday morning and repeated his claim, without evidence, that mail-in-voting was a disaster that enabled foreign intervention and fraudulent voting in the upcoming election. 

Trump additionally claimed that mail-in-voting would result in a far less accurate election as many US states push for an easier method of postal voting in light of the COVID-19 pandemic.

Trump's call to delay the election, in spite of it being enshrined in the US Constitution, comes at a time when he significantly trails Presumptive Democratic Nominee Joe Biden in the polls ahead of November's election.

A number of prominent Democrats have since condemned the president, labeling him as a liar and an authoritarian leader. 

Nancy Pelosi, the Speaker of the House, tweeted:

Ed Markey, a Democratic Senator representing Massachusetts, said that voting-by-mail had been proved safe and legitimate and called Trump an "authoritarian criminal" attempting to undermine democracy:

Meanwhile, Joe Kennedy III, a Congressman from Massachusetts who won Markey's vacant seat in the House of Representatives, labeled Trump a dictator:

Kennedy III previously tweeted:

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Former Democratic presidential candidate Bernie Sanders took a similar approach and called Trump's presidency a disaster. 

"No, Mr. President. We're not delaying the election. The American people are sick and tired of your authoritarianism, your lies, your racism. On November 3, 2020 democracy will prevail and your disastrous presidency will end. Bye-bye," Sanders said on Twitter. 

Joe Biden has yet to respond to Trump's tweet but did have this to say on Tuesday:

Any move to postpone or delay the election would require action by Congress, which holds the power to set the timing of the election. 

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