The World Cup kicked off in Qatar on Sunday with the Muslim nation, which faced a barrage of criticism over its treatment of foreign workers, LGBT rights and social restrictions, staking its reputation on delivering a smooth tournament.

Qatar's Emir Sheikh Tamim bin Hamad al-Thani arrived at the stadium flanked by FIFA president Gianni Infantino, to a roaring crowd, and took their seats alongside other Arab leaders.

A show then unfolded on the pitch, featuring three camels, American actor Morgan Freeman and a performance of a new tournament song called Dreamers featuring singer Jungkook of K-pop boy band BTS, alongside Qatari singer Fahad Al-Kubaisi.

Saudi Arabia's crown prince and the presidents of Egypt, Turkey and Algeria, as well as the United Nations Secretary-General, are among the leaders in attendance in a tent-shaped stadium ahead of the first match between the hosts and Ecuador.

Qatar, which has denied accusations of abuse of workers and discrimination, and FIFA hope the spotlight will now turn to act on the pitch. Organisers have also denied allegations of bribery for hosting rights.

Inside Al Bayt Stadium many seats were still vacant with gridlock on the expressway leading to the arena, where cheers went up as Qatar's team appeared for their opening match.

The football tournament, the first held in the Middle East and the most expensive in its history, is a culmination of Qatar's soft power push, after a 3-1/2 year boycott by Saudi Arabia, Egypt, the United Arab Emirates and Bahrain which ended in 2021.

The UAE, whose rapprochement with Doha has been slower than that of Riyadh and Cairo, sent its vice president who is also the ruler of Dubai, where many World Cup fans have opted to stay.

For the first time, a direct commercial flight from Tel Aviv to Doha landed in Qatar on Sunday despite the absence of formal bilateral ties, in a deal brokered by FIFA to carry both Palestinians and Israelis to the tournament.

The Gulf state's Deputy Prime Minister Khalid Al-Attiyah, in remarks on state media, said Qatar was reaping the benefits of years of “hard work and sound planning”.

On Saturday, FIFA president Gianni Infantino rounded on European critics of Qatar, saying engagement was the only way to improve rights, while Doha has also pointed to labour reforms.

Denmark's and Germany's team captains will wear One Love armbands as they prepare to compete in a conservative Muslim state where same-sex relations are illegal. Organisers say all are welcome while warning against public affection.

Throngs of fans were already arriving in Qatar but the main rush will be later this week.

Daniel Oordt from Holland, clad in orange, told Reuters there was a feeling of “constant pressure around you not to say the wrong thing or make the wrong move”.

“It's not a fun atmosphere to have at a World Cup.”

Argentina fan Julio Cesar though said he expected a great atmosphere. “We'll drink before the match,” he added after alcohol sales at stadiums were banned.

Visitors sipped beer at the FIFA Fan Festival in central Doha. Outside the city's edges, hundreds of workers gathered in a sports arena in an industrial zone, without alcohol. They can watch matches there, priced out of the stadiums many toiled to build along with other infrastructure for the event.

“Of course, I didn't buy a ticket. They're expensive and I should use that money for other things — like sending it back home to my family,” Ghanaian national Kasim, a security guard who has worked in Qatar for four years, told Reuters.

Gas exporter Qatar is the smallest nation to host football's biggest global event. Crowd control will be key with some 1.2 million visitors expected — more than a third of its population.

Workers were putting final touches to Doha's landscape, including draping a purple tarpaulin over an unfinished building near the stadium where the final will be held.

At Lagoona Mall, residents were going about their business.

“I came now because I don't know how bad the traffic will be later this week,” said Egyptian woman Esraa, grocery shopping

Benzema blow, Brazil arrive

All 32 teams competing at the World Cup have now arrived, with five-time champions Brazil the last to touch down in Doha late on Saturday.

Defending champions France suffered another injury hammer blow early Sunday after confirmation that star striker and Ballon D'Or winner Karim Benzema had been forced out of the tournament with injury.

The Real Madrid star limped out of a training session at the French camp on Saturday evening with a left thigh injury.

The French federation later confirmed in a statement that the 34-year-old would require “a recovery period of three weeks” and would play no part in the competition.

“I am extremely sad for Karim, for whom this World Cup was a major objective,” said France coach Didier Deschamps, who has decided not to replace the forward.

“Despite this new blow for the France team I have full faith in my squad. We will do all we can to rise to the huge challenge that awaits us.”

Benzema's withdrawal comes with France already battling the injury absence of star midfielders Paul Pogba and N'Golo Kante.

Belgium are also reeling from an injury blow after striker Romelu Lukaku was ruled out of the Red Devils' opening two games as he continues to recover from a hamstring problem.

Australia winger Martin Boyle joined the list of footballers who will play no part in the tournament. Head coach Graham Arnold said the winger had failed to recover from a knee injury.

“We all feel for Martin and it is a cruel blow for him,” Arnold said.