By Caroline Wyatt
BBC News, Paris
French Socialist presidential candidate Segolene Royal has called on President Jacques Chirac to restore order in the presidential election campaign.
Ms Royal's campaign has been damaged by a series of gaffes
She says her rival, Interior Minister Nicolas Sarkozy, has mounted dirty tricks and personal attacks on her.
The Socialists allege that Mr Sarkozy ordered the domestic intelligence agency to dig dirt on the former head of Greenpeace France, Bruno Rebelle.
He is now a member of the Royal team. Mr Sarkozy denies the allegation.
France's presidential election campaign has begun in earnest, with accusations and counter-allegations of dirty tricks.
Mr Sarkozy denies the Socialists' allegations
The Socialists are calling for Mr Sarkozy, the centre right UMP candidate, to resign as interior minister.
They say he misused his powers of office by ordering the domestic intelligence agency to investigate his rival's campaign team.
The man they were apparently interested in was a former director of Greenpeace in France, who now advises Segolene Royal on the environment.
Ms Royal's brother, Antoine, now claims that French intelligence also investigated him after he revealed that another brother, Gerard, was a French secret agent who helped blow up the Greenpeace ship Rainbow Warrior in 1985.
Mr Sarkozy denies ordering any such investigations.
However, some French commentators have called on the interior minister to step down, saying that his role as head of police and security is incompatible with running for the presidency.
The row could win Ms Royal some public sympathy, though she has recently seen her own campaign damaged by a series of foreign policy gaffes.
In the latest, she angered Canadians after apparently calling for independence for the French-speaking province of Quebec.
Ms Royal was then taken in by a French comedian, who telephoned her claiming to be the premier of Quebec.
Ms Royal's team have attempted to laugh it off. But more seriously, on a recent visit to Beijing, she sparked uproar in France by praising the Chinese justice system.