Zelensky came to Poland on Monday morning to hold talks with Tusk and President Andrzej Duda one day before a NATO summit in Washington on Tuesday to Thursday.
Tusk said after signing the deal that 19 countries and the EU had already signed similar agreements with Kyiv.
Both he and Zelensky wanted the agreement to be something more than just a declaration of good will, Tusk said, adding that the document included practical bilateral commitments, not just "empty promises."
All G7 countries and 25 other nations committed themselves to signing security agreements with Ukraine at the 2023 NATO summit in Vilnius, a guarantee of Western allies' support for Kyiv.
In June, the US and Japan signed similar deals with Ukraine. Six EU countries, including Poland, are now signatories to such security agreements and the EU as a whole signed a security deal with Kyiv in June. (PAP)
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