FIFA president Gianni Infantino said for the first time Thursday coronavirus containment measures could still be in place during the 2022 World Cup in Qatar but he insisted stadiums would be full.
In an interview with AFP ahead of the Club World Cup final he also suggested FIFA could "concretely" help travelling fans from countries where vaccine rollout has been slow or had not yet begun.
"Maybe some precautionary measures have to be taken," he said in the Qatari capital Doha, where Bayern Munich face Mexican side Tigres on Thursday.
"We need to see how the situation looks by then. It's very difficult to foresee now.
"It will take a little bit of time, and we have two years of time to come back to some sort of normality."
Infantino backed the Qatari hosts who in recent days have insisted the 2022 spectacle would go ahead with stadiums at 100 percent capacity, and he raised the prospect of FIFA assisting fans with vaccine requirements.
"If certain countries have difficulties accessing vaccines, in spite of the efforts of the World Health Organization... then we could certainly envisage helping them concretely with some projects targeting World Cup situations," he said.
"But two years from now I believe that, and I hope sincerely, that everyone who would like to be vaccinated will be vaccinated."
Infantino, who was speaking before reports emerged that Bayern forward Thomas Mueller has tested positive for coronavirus, praised Qatar for its execution of a bio-bubble during the Club World Cup.
Mueller would be forced to miss the final if his infection is confirmed.
"Football has resumed after being stopped in almost all countries in the world," said Infantino.
"One hundred percent security never exists, but we can do whatever we can to go very close to this.
"We are not the first organisation to organise an international tournament, after the outbreak of Covid-19, but it's a first World Cup that is taking place, because in 2020 unfortunately we were not able to organise anything."
He added that the pandemic had highlighted the challenges of a "congested" international match calendar.
"The real challenge for the future will be the international match calendar -- this balance between national team football and club football which is suffering even more now, during the Covid situation," he said.
Infantino also pledged further support for the global game which has lost more than $11 billion in revenue since the start of the pandemic according to FIFA estimates.
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