Estonian Prime Minister Taavi Roivas is asking for a permanent presence of NATO troops in the Baltic states.
"We need continuous presence of a battalion in Estonia, Latvia and Lithuania each," he is quoted as saying in the German newspaper Die Welt.
"There can't be any gaps. Deterrence has to be the new normality," he said.
In NATO's 1997 Founding Act, the military alliance agreed with Russia not to station a substantial number of troops in its Eastern member states on a permanent basis.
At a NATO summit in Warsaw in July, the military alliance is set to send troops to the Baltic states for regular training exercises, but exchanging the troops regularly.
Sending troops on a rotating basis is the right idea, Roivas said, "but they have to be present at all times."