King Felipe VI of Spain delivers a speech at the French National Assembly. Thierry Chesnot / Getty Images

King Felipe VI made an impassioned defense of the European Union during a three-day state visit to Paris on Wednesday.

Speaking in French, the Spanish monarch addressed the National Assembly and highlighted the country’s essential role in the European project. “Without France, there is no Europe,” he said.

The speech, which defended European unity in the face of growing nationalist sentiment in France and elsewhere, drew a standing ovation from deputies and ministers inside a legislative house that is rarely addressed by foreign leaders.

French Prime Minister Manuel Valls, who was born in Barcelona, joked about receiving a “Bourbon in the heart of the Republic”

It was a symbolic moment for Felipe VI, who is about to celebrate the first anniversary of his accession to the Spanish throne.

“Without a self-assured France that remains true to its values and stands firm in their defense, Europe and the world would lose a precious reference, a fundamental reference,” he told a house in which there is growing concern about the rise of the far-right Front National, which wants France to exit the euro zone and restore national borders.

“We want more France, to remind us that liberty, fraternity and equality are not given to us, but that we must fight for them every day,” said the king, whose father Juan Carlos is credited with saving Spanish democracy against a military coup in 1981.

This month also marks the 30th anniversary of Spain joining the European Union, then known as the European Community. Felipe VI said Spaniards are aware “of the value of an increasingly united Europe.”

Yet he also mentioned the problems facing the continent. “The European prosperity that we have enjoyed has been affected by an economic crisis that had very tough effects on the lives of our citizens. But the current circumstances must not make us lose sight of the essence of the European project. Europe must reassert itself and learn from its own principles and values.”

Terrorism was another major topic of his address. Five months after the jihadist attacks in Paris, which resulted in 17 deaths, France remains a priority target for radical Islamist groups.

“We Spaniards know very well what the French have felt and are feeling, because for decades we ourselves suffered and combated terrorism, and with their help, managed to defeat it,” he said, in reference to the Basque group ETA.

National Assembly President Claude Bartolone told Felipe VI that “we are in the house of the French people, which is always open to the king of Spain, as it was for his father and will be for his successors.”

During a lunch event held earlier in the day, French Prime Minister Manuel Valls, who was born in Barcelona, said the king was “the guarantor of the unity of Spain.” He also joked about receiving a “Bourbon in the heart of the Republic.”

Originally scheduled for March 24, the king’s official visit was suspended after Germanwings flight 9525 crashed in the French Alps.