Hungary remains the last obstacle to the Nordic country's NATO membership after Turkey's ratification last month, but its parliament is set to vote on Sweden's bid on Monday.

Following Russia's invasion of Ukraine, Sweden alongside neighbouring Finland applied to join NATO in May 2022.

"Welcome to Hungary, Swedish PM!" Orban posted on X, formerly Twitter, with a picture of him shaking hands with Kristersson.

After bilateral talks, a press conference is scheduled for around 11:30 am (1030 GMT).

The two leaders plan to discuss the strengthening of their "defence and security policy cooperation", according to a statement by the Swedish government.

This week, Hungarian pro-government news site Index reported that a "large-scale military and defence contract" between the two countries is in the works.

Hungary has a fleet of 14 Swedish-made Jas-39 Gripen fighter jets it operates under a leasing contract signed in 2001, which has since been extended twice.

Earlier on Friday, Orban told state radio that "some pending (bilateral) military and arms issues" had to be worked out before the Hungarian parliament on Monday "can put the final seal" on ratification.

"We are pro-peace, and the Swedes are pro-war in the Russian-Ukrainian conflict," Orban said but added that the "clear differences in values" could be bridged.

Faced with increasing pressure from the United States, as well as fellow EU member states to greenlight Sweden's NATO bid, Orban announced last week that Budapest was "on course" to ratify it.

Orban's nationalist Fidesz party -- whose ruling coalition with the Christian democratic KDNP holds a majority in parliament -- indicated it would support Sweden's bid on Monday.

All opposition parties except the far-right Our Homeland movement are in favour of ratification.

Although Hungary repeatedly said it supports Stockholm in principle, it prolonged the process by asking Sweden to stop "vilifying" Orban's nationalist government.

It has often denounced what it called Sweden's "openly hostile attitude", accusing Swedish representatives of being "keen to bash Hungary" on rule-of-law issues.

In January, Orban invited the Swedish prime minister to Hungary, citing the need to "build strong mutual trust" through "more intense political dialogue".

Finland became the 31st member of NATO in April 2023.