The EU warned Wednesday that France and five other countries were at risk of breaching the bloc's tough public spending rules, adding to the pressure on President Emmanuel Macron to push through tough reforms.

Brussels also sounded the alarm over Italy's high government debt in a fresh sign of concern over the eurozone's third largest economy, already buffetted by fears about its banking sector.

"The main message to France is the importance of correction of excessive deficit this year," Valdis Dombrovskis, the commission vice president responsible for the euro, told AFP in an interview ahead of the release of its assessment of EU states' budget plans.

Belgium, Italy, Austria, Portugal and Slovenia were also under fire for excessive deficits, the European Commission said.

The warnings come as the youthful Macron tries to push ahead with an ambitious programme of reforms aimed at rebooting the eurozone in the wake of the Brexit vote.

But his plans risk stalling after the collapse of coalition talks in Germany placed the position of Chancellor Angela Merkel, one of Macron's strongest backers, in jeopardy.

Macron has vowed to reduce public overspending with tough reforms and spending cuts.

French lawmakers approved his first annual budget with a thumping majority on Tuesday, as the president fends off accusations that his spending plans favour the wealthiest.

Dombrovskis and EU economic affairs commissioner Pierre Moscovici were meanwhile set to write to the Italian government, giving it until spring 2018 to bring things back in order.

"In the case of Italy, the persisting high government debt is a reason of concern," the European Commission said in a statement.