French President Emmanuel Macron compared France's choice in Sunday's presidential runoff to that of U.S. voters before they elected Donald Trump into the White House, whilst warning that his current polling lead was not a guarantee of victory.

"The next day they woke up with a hangover," Macron told BFM TV on Friday, saying that the situation in France is very similar as it involves a very fundamental choice about the direction of the country. He also pointed to opinion polls' inability to predict the outcomes of either the U.S. election or the Brexit referendum in 2016.

Surveys by France's leading pollsters published on Thursday and Friday showed support for Macron over far-right challenger Marine Le Pen stable or up slightly, albeit with turnout slipping to a historic low.