Biden says far-right Trump supporters a threat to democracy

President Biden has gone on the attack, calling far-right Republicans loyal to Donald Trump a threat to American democracy.

"Too much of what's happening in our country today is not normal," he told a crowd in Pennsylvania.

"Donald Trump and the MAGA Republicans represent an extremism that threatens the very foundations of our republic."

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The speech took place at Independence Hall and comes as Pennsylvania prepares to head to the midterm election polls in just a couple of months.

The state could tip the balance of power in Congress if it swings from Democrat to Republican.

It was also one of the states former President Donald Trump incorrectly claimed had fraudulent election results.

"I will not stand by and watch elections in this country be stolen by people who simply refuse to accept they lost," said Biden.

His 24-minute speech was aimed squarely at the MAGA-Republicans as he calls them, but his comments had raised the ire of the GOP before he'd even delivered his remarks.

"When the President speaks tonight at Independence Hall, the first lines out of his mouth should be to apologise for slandering tens of millions of Americans," said Republican minority house leader Kevin McCarthy.

Biden's approval rating is 44% - which recent history would suggest, means the Democratic majority in Congress could be about to be overturned at the upcoming election.

The President is pitching this as a critical turning point for the country.

"America must choose to move forward or move backwards," he said.

"To build a future, or obsess about the past... MAGA-Republicans have made their choice. They embrace anger, they thrive on chaos."

The speech was the third in the state this week - ahead of a visit by former President Trump this coming weekend.