Le Pen, who on April 24 faces President Emmanuel Macron in a run-off, said there should be a "strategic rapprochement" between NATO and Russia once the war launched by Moscow against Ukraine had ended.

"We must ask about the role of the alliance after the end of the Warsaw Pact," the Moscow-led military alliance that grouped Soviet bloc nations, she told journalists.

The news conference, designed to present Le Pen as a credible figure on the global stage, was briefly interrupted by a protester brandishing a heart-shaped picture of Le Pen and Russian President Vladimir Putin, who was quickly dragged out by security guards.

Le Pen emphasised that better ties with Russia would also prevent Moscow from becoming too close to China, noting that she was echoing an argument made by Macron in the past.

"This is in the interest of France and Europe but also I think the United States... which has no interest in seeing a close Sino-Russian relationship emerging," Le Pen said.

She also reaffirmed her intention to repeat France's 1966 move of leaving NATO's integrated military command, while still adhering to its key article 5 on mutual protection.

"I would place our troops neither under an integrated NATO command nor under a future European command," she said, adding that she refused any "subjection to an American protectorate".

On Europe, Le Pen made clear that any "Frexit" along the lines of Britain's exit from the European Union was not on her agenda.

But she argued that French predictions that Brexit would prove "a cataclysm for the English" had not come true.

"The British got rid of the Brussels bureaucracy, which they could never bear, to move to an ambitious project of global Britain," she said.

But she added: "This is not our project. We want to reform the EU from the inside."