Donald Trump has accused Twitter of interfering in the 2020 Presidential election after the social media platform fact-checked one of his tweets for the first time. 

It comes after Trump tweeted on Tuesday afternoon that mail-in ballots were 'fraudulent', claiming 'mail boxes will be robbed' in California, and as result the election will be 'rigged'.

He said: "There is NO WAY (ZERO!) that Mail-In Ballots will be anything less than substantially fraudulent. Mail boxes will be robbed, ballots will be forged & even illegally printed out & fraudulently signed. The Governor of California is sending Ballots to millions of people, anyone.....

“....living in the state, no matter who they are or how they got there, will get one. That will be followed up with professionals telling all of these people, many of whom have never even thought of voting before, how, and for whom, to vote. This will be a Rigged Election. No way!”

And now under the tweets, there is a link reading 'Get the facts about mail-in ballots' that takes users to a ‘what you need to know’ page with fact checks and media stories about Trump’s unsubstantiated claims. 

Trump has since responded in anger, saying Twitter is 'completely stifling free speech'.

He also threatened the company, stating that as President, he ‘will not allow it to happen’.

He wrote: "@Twitter is now interfering in the 2020 Presidential Election. They are saying my statement on Mail-In Ballots, which will lead to massive corruption and fraud, is incorrect, based on fact-checking by Fake News CNN and the Amazon Washington Post....

“....Twitter is completely stifling FREE SPEECH, and I, as President, will not allow it to happen!”

A statement from Twitter said: “These tweets contain potentially misleading information about voting processes and have been labeled to provide additional context around mail-in ballots.”

The US 2020 Presidential election is due to take place on November 8.