Nobel laureate economist Paul Krugman stated in a Substack blog post on Thursday that France is on a "fiscally unsustainable path," facing mounting interest on its government debt and exacerbating its high debt-to-GDP ratio with large budget deficits. He warned that France's reliance on the euro means that a loss of confidence could turn into an "ugly crisis," echoing the 2009-2012 sovereign debt crisis in Southern Europe. Krugman believes that bailing out France would be "extremely expensive" for the European Central Bank and politically contentious. Separately, former ECB head Jean-Claude Trichet told CNBC on Friday that French politicians must compromise to bring down the deficit of the euro area's second-biggest economy.