The prime minister of Poland, one of Europe's most critical voices on Russia, has held what she called "honest and difficult talks" with her Hungarian counterpart Viktor Orban, who faces sharp criticism in the West for cultivating closer ties with Russia.

Ewa Kopacz and Orban met Thursday in Warsaw, part of an effort by Orban to show that Hungary's growing closeness to Russia does not mean his country is turning its back on its Western alliance partners.

Orban's visit to Warsaw comes two days after Russian President Vladimir Putin visited Budapest, where he and Orban agreed to a new gas deal.

At a brief news conference alongside Orban, Kopacz said that in "honest and difficult talks" she stressed the importance of European unity in supporting Ukraine.