French far-right leader Marine Le Pen says the EU faces greater consequences than Britain from the "big bang" of Brexit — but she doesn't want France to leave the bloc.

Her plan to reform the EU into an alliance of nations must be adopted or "other countries will leave," she told Euronews.

Le Pen was once in favour of France leaving the EU. Her National Rally — formerly the National Front — used to support Frexit and she even promised a UK-style in-out referendum on membership.

However, her stance shifted amid a rebranding of her party in the wake of the 2017 presidential election loss to Emmanuel Macron.

Europe is a 'prison'

Instead, the Rassemlement National wants to recreate the EU as an "alliance of nations." Le Pen says that she believes far-right politicians within the EU now have the power to "radically modify" Europe.

"Maybe Great Britain can rejoin us once we've built something where each nation conserves their freedom," she said.

She still considers Europe to be a "prison" even if a member can leave it.

"[Brexit] still took three years ... there was a real contempt for the people on the part of leaders of the European Union who barely hid wanting to make the divorce as difficult as possible," she said.

Protectionism

Le Pen added that actions from other nations — including US President Donald Trump's efforts to place tariffs on some goods — prove that protectionism is the way forward economically.

"Today, we realise that, yes, we will have to negotiate effectively, and perhaps we too can do some form of economic protection for our own countries," Le Pen said.