The Court of Accounts, which audits spending in France, said intelligence provided by the UK to French police was often "first level" and "very general".
The UK is not passing on enough information about small boats crossing the Channel, a French report has said, reports the BBC.
The Court of Accounts, which audits spending in France, said intelligence provided to French police was often "first level" and "very general".
It said France needed more details about the boats and engines being used by criminal gangs.
The UK Home Office said the report used outdated information and didn't reflect the countries' current relationship.
The UK's National Crime Agency(NCA) said it had a close relationship with French law enforcement and border agencies.
But the Court of Accounts report on the battle against illegal migration concludes that the relationship between France and the UK is "unequal in terms of the exchange of information and intelligence".
