Lawmakers from Hungary’s ruling party have boycotted an emergency parliament session in which a vote on Sweden’s bid to join NATO was on the agenda, writes Al Jazeera.

At Monday’s session, which was supported by six opposition parties, Fidesz lawmakers didn’t attend, scuttling the attempt to place a vote on the National Assembly’s schedule.

Prime Minister Viktor Orban told NATO Secretary-General Jens Stoltenberg last month that he would urge his Fidesz party to ratify the bid “at the first possible opportunity”. On Friday, the US Embassy reminded Orban in a statement that he promised to act “at the first opportunity” and “Monday’s session provides him with one”.

Several ambassadors from NATO member countries attended Monday’s proceedings, including US Ambassador David Pressman. In brief comments to the media after the session, he said the US looks forward to “watching this closely and to Hungary acting expeditiously”.

“Sweden’s NATO accession is an issue that directly affects the United States’s national security and affects the security of our alliance as a whole”, he said, reminding Orban of his pledge.