France could have a public budget deficit above the government's target of 4.1 per cent of output in 2013, the auditors say, and is not likely to improve in 2014.
France's highly influential public accounts court, its president, Didier Migaud, says that efforts to cut public spending have to be "pursued and increased in the next three years".
The report from the court comes as the government tries to work out how to cut 50 billion euros spending by 2017.
This is to finance President François Hollande's promise to cut taxes and charges on businesses to regain competitiveness.
The court, which gives an overall assessment of the state of the public finances, also highlights selected cases of mismanagement and waste.
It mainly targets the health-care system and local and regional authorities, respectively 44 per cent and 19.5 per cent of budget costs.
Migaud estimated that five billion euros could be saved in the public health sector.
Education, local housing and social and economic welfare were also accusd of mismanaging spending.
In 10 years, 2002-2012, public spending has jumped from 816 billion to 1179 billion euros.
The country won extra time from the European Commission to gets its public deficit within the permitted ceiling of 3.0 per cent of gross domestic product (GDP).
France is the EU's second-largest economy and its finances are closely watched across the bloc, especially by Germany.