France's public debt has climbed to a record during the two terms of President Emmanuel Macron, unsettling investors and emerging as a defining issue ahead of next year's presidential election.

With France already gripped by deep social tensions, the candidates vying to succeed Macron are under pressure to explain how they would bring the debt under control. It now stands at 119% of gross domestic product, leaving the country's strained public finances likely to dominate the campaign.