"I think we're disappointed that ... Prime Minister Orban has chosen to stand alone in the European Union in questioning the fight to support Ukrainians," Jim O'Brien, the U.S. State Department's Assistant Secretary for European and Eurasian Affairs, told a Zoom briefing.

Hungary, a member of the European Union and NATO, has been refusing to provide military assistance to Ukraine since the full-scale invasion by Russia in 2022, as well as holding up Sweden's bid to join NATO alongside Turkey.

Orban's government has repeatedly promised that it will not be the last to ratify the Nordic country's bid to join the military alliance.

"We'll see if it follows through on that promise as we move ever closer to Sweden joining the alliance, which I hope will be soon," O'Brien added. "We would would like to see Hungary be a constructive partner."

The ratification of Sweden's NATO bid is not yet on the legislation's agenda for the spring session.

Relations between Budapest and Washington have soured because of Hungary's foot-dragging over the ratification of Sweden's NATO accession and also over Orban's warm ties with Moscow despite the war in Ukraine.

(Reporting by Boldizsar Gyori in Budapest and Luiza Ilie in Bucharest; editing by Barbara Lewis)