Four nations threatened in two weeks – Nato scrambles over Russian provocation

Putin's fighter jets and drones are testing defences across eastern Europe and the Baltics, forcing the alliance to confront existential questions

- Nina Kuryata

A fighter jet takes off from the USS Gerald R Ford, on manoeuvres in the North Sea last week.

(Federico Gambarini/dpa)

For Hanno Pevkur, 19 September was a satisfactory but still alarming day at the office.

By 10am word had reached him that three nuclear-capable Russian MiG-31 fighters were inside Estonian airspace tracking the country's northwest coast.

Within minutes, two Nato F-35 interceptors were airborne and close enough to the intruders to see the Russian pilots waving back at them. By 10.10am the Russians had left Estonia bound for one of their bases in Kaliningrad, but not before ignoring repeated orders to change course.

Pevkur, Estonia's defence minister, last week told The Observer the incursion was unprecedented for its duration and brazenness. But "we didn't see that there [was] an acute threat to our sovereignty or our security", he said, so no order was given to shoot the Russians down.

One of his colleagues says he was "perfectly happy" with Nato's response. The difficulty for Nato is that Russia's president, Vladimir Putin, also has reason to be happy.