President Joe Biden has warned Americans that his predecessor Donald Trump and his die-hard followers are trying to “undermine” democracy and asked them to confront the “extremists” who fan the flames of political violence in pursuit of power.

Delivering his sharpest rebuke yet of Republicans in a prime-time speech from the iconic Independence Hall in Philadelphia, where the US Declaration of Independence was signed nearly 250 years ago, Biden warned that the supporters of Trump’s “Make America Great Again” (MAGA) agenda are a threat to American democracy.

“As I stand here tonight, equality and democracy are under assault,” Biden, a Democrat warned, ahead of crucial mid-term elections in November that will determine control of Congress.

“Too much of what’s happening in our country today is not normal. Donald Trump and MAGA (Make America Great Again) Republicans represent an extremism that threatens our very republic. MAGA Republicans do not respect the Constitution,” the 79-year-old president said, in a rare instance of slamming his predecessor by name.

“There’s no question that the Republican Party today is dominated, driven and intimidated by Donald Trump and the MAGA Republicans, Biden said, referring to Trump’s 2016 campaign slogan, Make America Great Again.

“And that is a threat to this country,” Biden said.

“MAGA forces are determined to take this country backwards. Backwards to an America where there is no right to choose, no right to privacy, no right to contraception, no right to marry who you love. They promote authoritarian leaders. They fanned the flames of political violence,” Biden said.

In his 25-minute speech, Biden repeatedly called out Trump, who is still questioning the outcome of the 2020 election.

“History tells us that blind loyalty to a single leader and a willingness to engage in political violence is fatal to democracy,” he said.

He said he was not condemning all 74 million Americans who voted for Trump in 2020. “Not every Republican, not even a majority of Republicans, are MAGA Republicans,” he said.

Alleging that MAGA Republicans do not respect the Constitution, Biden called them “insurrectionists and election deniers” who “embrace anger and thrive on chaos”.

MAGA Republicans are a “clear and present danger to our democracy,” he alleged.

They live not in the light of truth but in the shadow of lies, Biden said.

“So, tonight, I have come to this place where it all began to speak as plainly as I can to the nation about the threats we face, about the power we have in our own hands to meet these threats, and about the incredible future that lies in front of us, if only we choose it,” Biden said.

“We must never forget that we, the people, are the true heirs of the American experiment that began more than two centuries ago,” he said.

Biden said Americans still believed in honesty, decency and respect for others. “Patriotism, liberty, justice for all, hope, possibilities, we are still at our core a democracy,” he said.

“For a long time, we’ve told ourselves that American democracy is guaranteed, but it’s not. We have to defend it, protect it, stand up for it, each and every one of us. That’s why tonight, I’m asking our nation to come together, unite behind the single purpose of defending our democracy regardless of your ideology,” Biden said in his national speech.

“We’re all called by duty and conscience to confront extremists who put their own pursuit of power above all else. Democrats, Independents, mainstream Republicans, we must be stronger, more determined, and more committed to saving the American democracy, and MAGA Republicans are just — they’re destroying American democracy,” he said.

“We, the people, will not let anyone or anything tear us apart. I want to say this plain and simple, there is no place for political violence in America,” Biden said.

MAGA republicans do not believe in the rule of law. They do not recognise the will of the people, Biden said.

“They refuse to accept the results of a free election and they are working right now as I speak in state after state to give the power to decide elections in America to partisans and cronies, empowering election deniers to undermine democracy itself,” he said.

Trump supporters thought of the mob who stormed the US Capitol last year as patriots rather than insurrectionists, he said.

“They look at the mob that stormed the United States Capitol on January 6th brutally attacking law enforcement, not as insurrectionists who placed a dagger at the throat of our democracy but as patriots, and they see their MAGA failure to stop a peaceful transfer of power after the 2020 election as preparation for the 2022 and 2024 elections,” Biden said.

His remarks come as Trump, once again at the center of a criminal investigation this one involving classified documents lays the groundwork for a potential 2024 presidential run.

Biden’s address comes two months before mid-term elections, which will decide the power balance in Washington.

House Minority Leader Kevin McCarthy, in the Republicans’ rebuttal speech, called on Biden to apologise for a remark calling MAGA philosophy semi-fascism.

“President Biden has chosen to divide, demean and disparage his fellow Americans. Why? Simply because they disagree with his policies. That is not leadership,” he said.

Last week, Biden equated what he called “extreme” Republicans with “semi-fascism”.

House Speaker Nancy Pelosi praised Biden for his inspiring and optimistic remarks in which he made crystal clear that their rights and freedom are on the line.

“The American people are rejecting the Republicans’ extreme MAGA agenda, and instead, choosing the Democrats’ unifying vision of ‘People Over Politics’,” she said.