VATICAN CITY

Pope Francis has urged Europe to build bridges instead of walls to stop refugees from entering their countries.

In remarks made during his flight from Philadelphia to Rome on Monday, the pope said: "You know what happens to all walls. All walls fall. Today, tomorrow or in 100 years, they will fall. The wall is not a solution."

Without naming Hungary, the pope added: "In this moment, Europe is in difficulty, it’s true. We have to be intelligent. We must find solutions. We must encourage dialogue between different nations, to find them. Walls are never solutions. But bridges are, always, always."

Europe is facing its biggest refugee crisis in decades, with thousands of asylum seekers from Middle Eastern and African countries trying to reach the continent.

Hungary, in particular, has been on the frontline of the latest crisis, as the central European country placed a series of restrictive measures resulting in extremely limited access for refugees at the border.