Secretary General Jens Stoltenberg, May 18, 2016 (photo: NATO)

In an interview with the Guardian at Nato headquarters in Brussels, Jens Stoltenberg, the secretary general, also warned that a “fragmented Europe” would exacerbate “instability and unpredictability” in the region. …

“What I can do is tell you what matters for Nato, and a strong UK in a strong Europe is good for the UK and it’s good for Nato, because we are faced with unprecedented security challenges, with terrorism, with instability and an unpredictable security environment, and a fragmented Europe will add to instability and unpredictability….”

Many Nato officials are concerned that what they see as the two biggest threats to European security – Islamic State together with other Islamic extremists, as well as a newly aggressive Kremlin – both have the fragmentation of Europe as a strategic goal.

“The UK is the biggest force provider among European Nato allies so it matters what the UK does and for Nato it is an advantage to have UK leadership inside the European Union being a strong advocate for transatlantic cooperation and also for EU-Nato cooperation,” Stoltenberg said….

“To fight the terrorist threat we need both the EU and Nato and we need stronger cooperation between Nato and the European Union,” he said. “And the UK is pushing and showing leadership in pursuing that both from inside Nato and from inside EU. If our neighbourhoods are more stable we are more secure.”

“The UK is a kind of bridge between the EU and Nato and also a bridge between Europe and the United States. And this is important for UK, the US and for Nato,” he said. “No one of us has all the tools in the toolkit so we have to work together and the UK is a key ally in facilitating that….”