EU Minister: Brexit would heighten risks from 'aggressive and truculent Russia'
Part of the UK's role in Europe is to "keep the EU focused on the growing challenges posed by Putin's Russia," Lidington said in London on Thursday at the FT's Europe conference.
"The role of NATO is key, and the UK's role in that is to ensure that the EU is aligned with that. It's a major diplomatic and security challenge to make sure that the relationship between the EU and US is strong, and that's now more important today than at any point during the Cold War," Lidington said.
Britain votes on whether to leave the EU in 10 weeks time, with most polls showing the result is too close to call at the moment.
The political campaigns start on Friday "but it feels like it's been going on for a long time," Lidington said.
His comments come a day after two Russian warplanes with no visible weaponry flew simulated attack passes near a US. A US official said it was one of the most aggressive interactions in recent memory.
The repeated flights by the Sukhoi SU-24 warplanes, which also flew near the ship a day earlier, were so close they created wake in the water, with 11 passes, the official said, according to Reuters.