The EU and New Zealand sealed a free trade deal on Thursday after four years of talks, promising it would protect the environment and unite like-minded partners amid international turmoil.

"This is a historic moment in our cooperation," EU commission chief Ursula von der Leyen told reporters at a joint appearance with New Zealand's Prime Minister Jacinda Ardern, adding that the deal had come after  "tough negotiations".

Ardern hailed a  "historic further milestone in the strong partnership between two closely-connected like-minded friends."  "And while this is an incredibly important day for our trade relationship, it's also a time to acknowledge the extraordinary time and challenges that Europe is facing," she added.