In an interview with the Financial Times, Lieutenant General Riho Terras, Estonia's commander-in-chief, said an inadequate air defence capability made the Baltic region vulnerable to a Russian lightning attack, Censor.NET reports.
According to him, Nato needs to consider increasing the number of warplanes it has based in the region, and plan for the deployment of Patriot batteries.
"Of very great importance is our self-defence capability... what we need [for that] is air defence capability," said Gen Terras. "We need to be ready and we need to look at what we need to do. Russia behaves opportunistically. If they have the opportunity, they'll jump through the window to take it."
"The Baltic states can be seen as an island," said Gen Terras. "The gap is small... there's one railway and two roads going through it."
Basing new battalions there was a strong first step, said the general, but Nato also needed to develop its own anti-access aerial denial, or A2AD, strategy such as powerful surface-to-air missile systems - that the alliance has long feared Russia could use in the region.
Nato military chiefs say Russian missile systems in Kaliningrad have carved out an "A2AD bubble", making it hard for the alliance to manouevre its forces anywhere in the area, even deep within its own territory.