Leaders of Italy, France, Germany meet to launch post-Brexit path

On Monday, their talks also focused on terror threats, and the ways to improve security at the bloc's internal and external borders.

"The idea of a European defense takes on an absolute crucial relevance now, since we are facing internal threats and wars in countries near us," Hollande told the press conference.

"We are not here to take decisions for others (EU members), but to prove we are ready to take on our responsibilities, as EU's three largest countries, in order to bring Europe towards a future of greater cohesion and unity," the French president added.

The talks in Ventotene island also aimed at preparing the ground for an informal EU summit scheduled in Bratislava for Sept 16, in which all EU leaders but the British prime minister will discuss the effects of the Brexit vote on the economy.

"Further growth and development is another big issue (to tackle), since we know Europe is not a most competitive place in all of its contexts," Merkel stressed.

"We will have to address this in Bratislava, and also discuss the future of our youth, who must have the chance to play a role, and bring European values around the world," the German chancellor added.