Rod Henderson, head of coastal operations for the the Marine Management Organisation, said:
As soon as the MMO was made aware of the situation, our officers contacted the French authorities and encouraged them to intervene. They did and are continuing to deal with this matter.
It is the responsibility of the French authorities to ensure the safety of UK vessels in their waters. Had the situation occurred in UK waters, the Royal Navy would have responded.
Royal Navy fisheries protection vessels do sometimes cross the median line into French waters where a joint operation has been pre-agreed. The next joint operation is already scheduled, and the Royal Navy may soon have a presence in the area as part of this patrol.
The MMO is continuing high-level discussions with French counterparts to seek assurances that these issues will not recur.
The MMO is also liaising with the Maritime and Coastguard Agency, which has responsibility for collision at sea regulations, to resolve this issue.
British boats are entitled to fish in the area, 20 miles north west of Le Havre, even though it is in French waters.
The area had recently been closed off to French vessels by local authorities but was reopened on October 1, the spokeswoman said. UK boats were still entitled to enter the waters during the "closure" period.
The MMO spokeswoman said one reason the closure could have been put in place was so scallop stock levels could be replenished.
The situation was eventually defused after the MMO contacted the French authorities, who intervened.