The 188 included all 135 MPs from the ruling Fidesz party and its satellite, the KDNP party, as well as pro-Western opposition MPs.

The six nay-sayers came from the neo-Nazi Our Homeland Party.

Orbán himself gave a “brief and empty speech to start” the day’s proceedings, according to Iván László Nagy, a journalist at the HVG weekly in Hungary and an expert at the Visegrad Insight think-tank in Warsaw.

The debate livened up briefly when opposition MPs began calling his party “paedo-Fidesz” and complaining that Orbán had kept silent on Russia’s killing of its world-famous dissident Alexei Navalny on 16 February.

The paedophilia jibes came after the Hungarian president, who was from Orbán’s ultraconservative Fidesz party, resigned in a scandal on 10 February after wrongfully pardoning a child-abuser.

Meanwhile, Orbán is the last EU leader still willing to shake Russian president Vladimir Putin’s hand, even though Putin is wanted for war crimes by the International Criminal Court in The Hague.

“They [Fidesz MPs] looked very defeated,” said Hungarian opposition MP Ágnes Vadai, speaking of the atmosphere in Monday’s vote despite the near-unanimous outcome.

Orbán had held out to become the last of 31 Nato allies to ratify Sweden’s entry, amid Russia’s war in Ukraine.

He and his Fidesz loyalists had loudly complained about Swedish insults to Hungary’s honour, after Stockholm had criticised Orbán’s abuse of rule of law in Hungary.

He even sent a delegation of Fidesz MPs to Sweden last March, saying Stockholm was to help him unfreeze billions of euros being held back in European funds for Hungary due to EU concerns about judicial independence.

But in the end, he got much less before he backed down, amid mounting US pressure.

Sweden upgraded an arms contract with Hungary and Swedish prime minister Ulf Kristersson visited Orbán in Budapest last Friday in a face-saving side-deal instead.

“Orbán got four more Swedish Gripen fighter jets and obliged the Swedish leader to visit Budapest, which he was reluctant to do,” said Jamie Shea, a former Nato official who now teaches war studies at Exeter University in the UK.

That was enough to “portray it as a victory at home which is what matters to him”, Shea said.

And if Fidesz MPs appeared “defeated” on Monday to Vadai, from the opposition Democratic Coalition party, then the subdued atmosphere might have been due to their apathy rather than their low morale.

“Fidesz have a supermajority, so the right to pass any legislation they want. Everyone else is just there for show,” said László Nagy.

“You can hardly look defeated if you can pass anything without anyone else’s support,” he said.

For their part, EU and Nato leaders welcomed the Hungarian outcome in posts on social media.

“The way is clear for Sweden to join Nato — a win-win situation for us all,” said German chancellor Olaf Scholz.

Sweden’s Kristersson said: “Sweden stands ready to shoulder its responsibility for Euro-Atlantic security”.

The legal niceties of Sweden’s entry, which require Hungary and Sweden to deposit signed documents at the Nato HQ in Brussels, can now be completed in a few days’ time.

The Nato enlargement will see swathes of strategically important territory in the High North and Baltic Sea fall under the Western security umbrella, despite Putin’s threats against Western expansion.

It comes two weeks before the Russian president runs for re-election on 15 March.

But the outcome of the Russian vote was a foregone conclusion, after Putin killed, jailed, or disqualified his opponents, with the Sweden-Nato move unlikely to dent his strongman image, said Shea.

“He [Putin] factored in Sweden some time ago and played it down. It won’t cost him votes, and the result of the election is hardly a cliffhanger,” Shea added.