Defence Secretary Gavin Williamson, who watched the helicopters as they left the Wattisham Airfield in Suffolk, said the deployment is about “adapting to a changing situation.”

"It's a very credible threat that we see from Russia and part of the reason that we're deploying five Apache attack helicopters is making sure that we're constantly adapting to a changing situation,” Williamson said.

"But this is about deterrents,” he added.

He said: “This is about NATO nations standing together in unity as one and you see Great Britain playing the largest role in enhanced forward presence with the largest number of service personnel deployed.”

"The enhancement of that deployment with the Apache attack helicopters is really vital and very, very important and it's been very warmly welcomed by so many nations," he added.

The Apaches will be “working in tandem with the Army’s Wildcat battlefield reconnaissance helicopters to provide valuable training opportunities to NATO allies on Estonia’s annual Exercise Spring Storm” and “to the UK-led battlegroup deployed on NATO’s enhanced Forward Presence,” according to a statement from British Ministry of Defense. ■