Hungary and Turkey are the only two NATO countries that have yet to ratify Sweden's and Finland's membership bids.

Budapest is expected to vote in favour of both countries joining the alliance "in the coming weeks", the deputy speaker of the Hungarian parliament Csaba Hende told reporters in Stockholm.

"We started the debate last week and normally when everything goes well, in a couple of weeks time such a debate is over", said Hende, who is a member of Prime Minister Viktor Orban's Fidesz party.

Hungary's repeated ratification delays have raised concerns in Sweden and Finland, whose bids are already being held back by Turkey.

According to the Hungarian parliament's website, the vote was initially due to take place between March 6 and 9 but has now been pushed back to March 20 at the earliest.

Hende and other Hungarian MPs on Tuesday met with the Swedish speaker of parliament for a "courtesy visit".

"It was warm, friendly, forward-looking, and carried with it the hope of a new beginning", Hende said.

"We made it clear that the Hungarian government, the Hungarian president, and the vast majority of MPs unanimously support the NATO membership of Sweden", he said.

But he noted it was "necessary" to improve bilateral relations between Stockholm and Budapest.

Sweden also needed to show Hungary "more respect", he said, accusing Sweden of spreading "lies".

"It would be good if in the future, Swedish politicians, members of government, MPs and MEPs would avoid portraying Hungary in a false light by eluding to an absence of rule of law that is based on clearly untrue facts", he said.

Sweden is concerned that Hungary could use its NATO bid as leverage in its battles with the European Union.

In December, Brussels froze billions of euros worth of funds pending anti-corruption reforms expected from Budapest.

The Hungarian government has also, unlike the rest of Europe, trod an ambiguous path on the war in Ukraine and has refused to criticise Russian President Vladimir Putin by name.