WARSAW, April 3 (AFP) - Ukrainian President Volodymyr Zelensky is to make an official visit to Warsaw on Wednesday, said Poland, announcing one of his few trips outside his nation battling Russia's invasion.

NATO member and neighbour Poland is a key ally in Kyiv's effort to defend itself, and has hosted many Ukrainians fleeing the war.

"This is an official visit but there will also be an element of a public nature," the head of the international policy office, Marcin Przydacz, told Polish radio station RMF FM, noting that Zelensky would also meet Ukrainians living in Poland.

During the visit, Zelensky will meet his Polish counterpart, Andrzej Duda.

Zelensky is to deliver remarks in the historic centre of the Polish capital, "in the context of what happened last year -- how the Poles are helping Ukraine, refugees at the border, or welcoming them into their homes".

Discussions with Polish Prime Minister Mateusz Morawiecki are also planned.

Before Warsaw, the Ukrainian president has already visited Washington, London, Paris and Brussels.