French investigators are probing allegations of embezzlement involving high-profile presidential candidate Edouard Philippe over the allocation of a digital hub contract in the northern port city of Le Havre where he is mayor, prosecutors have said.

The 55-year-old centrist, an ex-prime minister seen as one of the strongest contenders in next year's election to replace President Emmanuel Macron, denies the accusations.

Polls suggest that Philippe, a centrist with his Horizons party, could successfully take on the far right and win the vote.

His team told AFP that he took note of the probe and would "answer the questions put to him by the judiciary as he has always done in a very serene manner".

Contacted by AFP, his lawyer did not wish to comment.