In order to strengthen deterrence in the Baltic countries and the alliance's eastern flank, NATO has to focus on establishing a trustworthy system of reinforcement forces and practicing this, officials and experts said at the Lennart Meri Conference on Sunday.

Speaking at a discussion held under the Chatham House Rule, one panelist said that NATO has learned deterrence again in the past four years, and now when there are allied battle groups in the Baltic countries, a system of reinforcements has to be focused on.

"We have to ensure that NATO's Very High Readiness Joint Task Force (VJTF) is indeed ready to move as a first wave and the NATO Response Force (NRF) is there as a second wave," the expert said.

Updating the military leadership structure and strengthening the eastern flank are among the main topics to be discussed at the upcoming Brussels Summit, which will take place on 11-12 July.

According to another speaker, the battle groups stationed in the Baltics and Poland would need additional reinforcements during a crisis, and the Baltic states would have to fill the gaps themselves which would allow for the bringing of additional units to the region.

According to a third speaker, the U.S. Navy once again takes protecting the Atlantic Ocean and waterways there seriously. NATO naval forces have made a transition from security providing missions to warfighting readiness, and more large-scale naval exercises would be needed in the future.

The panelist said that should deterrence against Russia fail, the U.S. needs to come back into Europe in a massive way.

According to one speaker, history has demonstrated that there is no Baltic-based solution to the defence of the Baltic states, and it is destined to fail. Instead of constantly trying to increase the size of our forces, we have to act in a more clever way, they said.

The panelist said that Estonia's defence ability is based on three pillars — the country's own defence, alied presence, and reinforcement.

The panelists emphasised the importance of increasing defence spending to at least 2% of the GDP, as agreed upon in NATO, and the importance of this topic at the upcoming NATO summit. They also expressed hope that there would be no major political disputes at the summit that would overshadow the real work of the alliance.