Andrzej Duda made the declaration in a video message to Ukrainians released on Tuesday, Polish state news agency PAP reported.
November 21 marked 10 years since the start of popular protest that swept pro-Russian President Viktor Yanukovych from office in February 2014, signalling a pro-Western turn in Ukraine.
Poland's president said that in the revolution of 2014, the people of Ukraine expressed their "desire to be independent from the eastern neighbour" and "an integral part of the Western world."
Duda noted that Russia had reacted by annexing the Ukrainian peninsula of Crimea and backing a militant insurrection in the eastern Donbas region, before launching "the full-scale aggression we are witnessing now."
The Polish president said that Poland had supported Ukraine's pro-European revolution of 2013-2014 and was the first country to call for Kyiv "to be granted the status of candidate to join the EU" following Russia's February 2022 invasion.
Duda noted that the EU's executive Commission earlier this month recommended that the bloc open accession negotiations with Ukraine.
He congratulated the Ukrainian people, describing Brussels' move as "a big success" for Kyiv.
The Polish president declared: "Poland will steadfastly stand shoulder to shoulder with you, and support you in your fight against the aggressor."
He added: "We'll be helping you on your path to the EU and NATO because we would like to see you in our European family as soon as possible."
Duda said that "a free and independent Ukraine" and a partnership with Ukraine were "of fundamental importance" to Poland.
The Polish president said he was confident that both countries would "further develop" bilateral relations "in this spirit," the PAP news agency reported.
Wednesday is day 637 of Russia’s war on Ukraine.
Russia invaded Ukraine on February 24, 2022, launching the largest military campaign in Europe since World War II.
(pm/gs)
Source: PAP, prezydent.pl