Tusk met with Estonian Prime Minister Kristen Michal in Warsaw on Wednesday.
"Both our countries are very active in creating a political scenario that allows for the termination of the war in way that is just and acceptable to both Ukraine and allies, and notably in a way that would be in line with our interests and security," Tusk said at a joint press briefing with Michal.
Tusk went on to say that he and Michal had discussed actual threats and challenges for Poland and Estonia as well as the activities undertaken by both countries, including the collaboration with the group of Nordic and Baltic countries "which Poland also joined."
Other topics discussed included cybersecurity and the recent elections in Romania, which have raised concerns of Russian interference, according to the Polish prime minister.
The elections have confirmed "Russia's constant readiness to launch attacks with the use of increasingly sophisticated tools and operations," Tusk said.
"With increasing efficiency, they are trying to interfere in the life and political decisions of European countries," Tusk added.
Michal expressed a positive view of Tusk's proposal to deepen cyber-cooperation between Poland and Estonia. "I believe it's an excellent idea," he said.
"We must strengthen the European Union's defence capabilities and remember that nothing should be arranged about Ukraine without Ukraine's participation," Michal added.
He also expressed hope that the EU would be able to pass yet another package of economic sanctions against Russia.
"We must hit the Russian war machine where it hurts most, its energy dimension," Michal said.
He also mentioned that Poland and Estonia understood the challenges of having Russia as their neighbour.
"It is a crucial moment for our region's voice to become Europe's voice," Michal said. (PAP)
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