"The prime minister was clear that while the UK is leaving the EU, we are not leaving Europe," a Downing Street statement said. "They [the two prime ministers] agreed on the need to maintain our close cooperation on security and defence, including through Nato."
Cazeneuve called for a "clear method" for negotiating Brexit once Article 50 of the EU's Lisbon Treaty is triggered, probably before the end of March.
"Then, once the terms have been clearly discussed and negotiated, we can talk about the new relationship," he told the media.
With Cazeneuve anxious about the status of the 300,000 French nationals currently living in Britain, May's statement promised "an early agreement on the rights of EU citizens in the UK and UK citizens in the EU".
Migrant minors cold-shouldered
But French sources said that Cazeneuve called for Britain to reexamine the cases of the thousands of minors who are trying to be admitted to its territory from France.
The UK government last week said it would accept a further 350, far below the 3,000 figure initially floated, causing dismay among NGOs who point out that many of the applicants' families have already crossed the Channel.
The Jungle was closed at the end of last year and its residents sent to centres across France.
The two prime ministers also discussed unrest in Syria and Ukraine, migration and terrorism.
To see A history of the Jungle in pictures click here