Prime Minister Viktor Orban's ruling Fidesz party "supports Finland's NATO accession," said Kovacs, citing the party's parliamentary group leader Mate Kocsis.

"The parliamentary vote will take place on March 27," Kovacs said in a Twitter message.

While Kocsis said in a Facebook message that "the parliamentary group will decide on the case of Sweden later."

Turkey and Hungary are the only NATO members still to ratify Sweden and Finland's bids, which must be accepted by all 30 existing members of the military organisation.

At the beginning of March, Hungarian lawmakers started debating the NATO bids of Finland and Sweden, but the parliament - dominated by Fidesz - had dragged its heels on setting a date for the vote.

Hungary "will not bow to pressure...regarding when and how parliament should approve legislation," said Kocsis.

A Hungarian parliamentary delegation that visited Stockholm and Helsinki last week said Swedish politicians need to stop spreading "lies" about Budapest and the rule of law.

Budapest has been at loggerheads with Brussels for months over blocked EU funds earmarked for Hungary as Brussels insists on anti-corruption reforms and rule-of-law guarantees.