Donald Trump's biggest European fan, Hungarian Prime Minister Viktor Orbán, predicted on Friday that a new U.S. administration under Trump will cease providing support to Ukraine in its fight against Russia's full-scale invasion.

Europe will need to rethink its support of Ukraine if Donald Trump is elected president of the United States, Hungarian Prime Minister Viktor Orban said on Sunday, as the continent "will not be able to bear the burdens of the war alone".

Orban, who has grown increasingly isolated within the EU for his ties with Russia and opposition to military aid for Ukraine, has praised Trump as a "man of peace" who would quickly end the war. The two spoke by phone late on Wednesday, and Orban posted on social media: "We have big plans for the future".