France's public deficit for 2013 stood at 4.3 percent, higher than the 4.1 percent forecast by the government, the newspaper Les Echos said on its website on Sunday.
The official figures will be released on Monday by the National Institute of Statistics and Economic Studies.
If confirmed, it will provide yet further bad news for President Francois Hollande following catastrophic local election results on Sunday, which saw his Socialist party trounced by the centre-right UMP as well as gains for the far-right National Front.
Earlier this month, the executive European Commission placed France under close watch over its failure to rein in its deficit.
France has promised to get the deficit to a projected 3.6 percent in 2014 and 2.8 percent next year.
But the Commission, which predicted Paris would not meet the 2013 target, also said it would fail to hit the 2014 figure.
Les Echos said the institute will announce on Monday that public debt reached 93.5 percent of GDP last year, against 90.2 percent in 2012.