The political turmoil in the United States, where Donald Trump on Wednesday became the first president in U.S. history to be impeached twice, has served as an alarm to Western democracies, France's finance minister said on Thursday.

When Trump leaves office, he will leave behind a nation deeply divided over his brash brand of populist politics and economic nationalism that he promised would 'Make America Great Again'.

Ten Republicans joined Democrats in the House of Representatives to charge him with inciting an insurrection in last week's violent rampage in the Capitol.

"What is happening now in Washington is I think the greatest event that we have (experienced) in Western democracies," Finance Minister Bruno Le Maire said in an interview at the Reuters Next conference.

"Having this kind of event should be a kind of alarm for all European and all Western democracies."

France holds a presidential election in spring of 2022. President Emmanuel Macron's most likely main challenger will be Marine Le Pen, leader of the far-right Rassemblement National (National Rally) party.

For years, Le Pen has espoused a brand of economic nationalism that is anti-Europe, anti-immigration, and anti-globalization.

She was soundly beaten by Macron in the 2017 presidential run-off vote, but his term in office has been mired in social unrest, and pollsters project a closer contest next year were the two to go head-to-head again.

Le Pen touted Trump's 2016 election win and Brexit as a harbinger for the rise of populism in France elsewhere in Europe, and had not recognized President-elect Joe Biden's poll victory prior to the storming of the Capitol — a scene which she described as "extremely shocking."

Le Maire said he trusted fully in U.S. democratic institutions and the country's ability to overcome its difficulties.

"Democracies are fragile," he cautioned. "We should be aware of that."