The UK was no longer "isolated" from the continent, Lévy said – not least because of the Channel Tunnel – and Brexit would not change this.
"It’s too bad that the UK has decided to leave Europe, it’s too sad for the future," he told a press conference in London this morning to launch the second VivaTechnology festival, which takes place in Paris in June.
"But I believe that for the entrepreneurs, there are no fences. The collaboration [among start-ups] is much stronger than any fence, any barrier."
Organised by Publicis Groupe with news media company Les Échos Group and billed as "the world’s rendez-vous for game-changers", VivaTechnology aims to set itself apart from other tech industry events like South by Southwest and Mobile World Congress with a strong focus on connecting entrepreneurs with funders, mentors and corporate partners.
Its conference program includes the likes of PayPal chief executive Dan Schulman, Alphabet (Google) executive chairman Eric Schmidt, and Alibaba chief executive Daniel Zhang, while the show promises 20 exclusive product launches.
The first two days are industry only, but unlike most other events of its kind, it is open to the public on its third and final day, 17 June.
Publicis Groupe confirmed in January that Lévy would step down as chief executive at the start of June, becoming chairman of the supervisory board and handing over to Arthur Sadoun.
Lévy was joined at the event by Ronan Harris, UK managing director of Google, one of the four top-level sponsors of the event.
Harris acknowledged that the 18-year-old Google, one of the world’s five biggest companies by market capitalisation, could hardly be considered a start-up anymore, but said the company does "believe very much in the mindset of start-ups and supporting the ecosystem – it’s not that long since we were one ourselves."
He highlighted how crucial it was for the economy to fully support the start-up ecosystem, suggesting that in the last decade, all of the net job creation has come from companies less than five-years-old.
This did not just mean capital support though, Harris argued, but a shift in education and training to ensure new companies could find the human resources they need.
"Not just in the UK but right across Europe we see a shortage in the field of digital skills," Harris said. "80% of companies in the UK see this, and the EU predict there will be up to a million unfilled jobs by 2020 unless we address that gap."