The leaders of Finland, Sweden, Norway, Iceland, Denmark, Estonia, Latvia and Lithuania -- the Nordic-Baltic Eight (NB8) regional cooperation format -- met as the transatlantic alliance prepares for its own summit in Turkey next month.

"Ukraine is a strategic security partner to NATO, contributing directly to Euro-Atlantic security through its battlefield experience, technological innovation and industrial capacity," the NB8 leaders said a joint statement.

"We support Ukraine on its irreversible path to full Euro-Atlantic integration, including NATO membership," they added.

Ukraine is expected to take part in the Ankara summit, which comes as NATO's European members fret over US President Donald Trump's commitment to the alliance.

Russia's full-scale invasion of Ukraine in 2022 prompted Sweden and Finland to abandon decades of military non-alignment and join NATO.

NATO's top military commander in Europe declared the alliance's northeastern flank to be "one of the most strategically significant" areas in the world, and work is under way to boost defences.

On the sidelines of the Tuesday summit in Tallinn, Latvian Prime Minister Andris Kulbergs and Zelensky signed a cooperation agreement on drones, according to the BNS news agency.

The deal outlines technological and industrial exchange between the two states, which allows Latvia to use Ukraine's battlefield know-how in drone technology.

Since the start of the war in Ukraine, Baltic countries -- which have a long land border with Russia -- have faced growing pressure from hybrid threats, including drone incursions into their airspace.

French NATO jets shot down a drone in Latvia on Monday, and President Emmanuel Macron joined the NB8 summit by video link.

Macron told the leaders that as Russia's offensive was failing in Ukraine, the Kremlin was seeking to provoke its neighbours.

"We will face them together," he said.