Demonstrations were held in several cities, including New York and Washington DC, and remained largely peaceful, police said.

According to organisers, nearly seven million people participated in over 2,700 events across all 50 states, marking one of the largest coordinated protests since Trump returned to power for a second term last year.

In New York, thousands gathered at Times Square holding placards that read “Democracy, Not Monarchy” and “The Constitution Is Not Optional.”

The New York Police Department said more than 100,000 people joined rallies across all the five boroughs.

“We had more than 100,000 people across all five boroughs peacefully exercising their First Amendment rights,” the NYPD posted on X.

Ahead of the demonstrations, Trump allies accused the protesters of being linked to the far-left Antifa movement and labelled the nationwide rallies as “anti-American", media reports said.

Since taking office earlier this year, Trump has expanded presidential powers through a series of executive orders that critics say undermine democratic institutions.

His administration has also faced backlash over immigration crackdowns and cuts to federal healthcare programs.

Beth Zasloff, a writer from New York, told the BBC she joined the protest out of concern over “a move toward fascism and authoritarian government.”

“It gives me hope to be out here with so many people,” she said.

Massimo Mascoli, a 68-year-old retired engineer from New Jersey who grew up in Italy, said he feared the U.S. was “following the same path” his home country did under fascist rule.

“We cannot count on the Supreme Court or Congress. All three branches of government are against the American people right now,” he told the BBC.

Several Democratic leaders expressed support for the protests. Senate Minority Leader Chuck Schumer wrote on X: “We have no dictators in America, and we won’t allow Trump to keep eroding our democracy.”

Vermont Senator Bernie Sanders also praised the turnout, saying: “Thank you to the millions of Americans who turned out in small communities and big cities all over this country to say loudly and boldly: No more kings. In America, we the people will rule.”

Solidarity demonstrations were also reported in Berlin, Madrid and Rome, where crowds expressed support for the American protesters.