French officials have rejected reports its intelligence agencies are running a vast spying operation on its citizens, BBC News said.

A spokesperson for Prime Minister Jean-Marc Ayrault said the claims in the French daily Le Monde were "inexact".

Le Monde reported that computer and telephone data were being stored on a supercomputer at the offices of the DGSE foreign intelligence service.

The programme operated "outside the law" and could be accessed by all domestic agencies, the paper said.