Fifa vice president Jeffrey Webb says player welfare is his main priority ahead of the Qatar World Cup in 2022.
Summers in Qatar can reach 50C and there is an ongoing debate as to whether it should be moved to winter.
His comments come as a university report suggests the 2022 Premier League season would have to be cut short to help England acclimatise.
"The real concern from my perspective will definitely be the conditions for the players," said Webb.
Earlier in the month Football Association chairman Greg Dyke said holding a summer World Cup in Qatar in 2022 would be "impossible".
Dyke, who took up his FA role last month, thinks the tournament is likely to move to winter because of the heat.
The Premier League opposes a change of dates, while Dyke's predecessor David Bernstein last week told the BBC there should be a "rebidding process" after earlier suggesting any switch would be "fundamentally flawed".
Qatar's World Cup organising committee says it is ready to host the tournament in summer.
But speaking to BBC Radio 5 Live's Sportsweek programme, Concacaf president Webb, one of eight Fifa vice presidents, said player welfare must come first.
"The World Cup is about the players and it's about showing them the necessary respect," he said.
"If we have to move it to the winter or are able to stay in the summer, let's do what's best for football."
A University of Bedfordshire study has analysed how England would prepare for the tournament.
And Professor John Brewer, who heads the university's Sports Science department, says studies show that a summer tournament in Qatar will only be possible with the right preparation.
"Physical performance and decision-making will be impaired in hot conditions," said Brewer, a former head of sport science at the Football Association, who was also a member of England's backroom staff at the 1990 World Cup.
"The research we have done in our environmental chamber has involved simulating the demands of football matches in environments that come close to replicating conditions in Qatar.
"The results are unsurprising; but we've also found that players' bodies could adapt to the extreme conditions if the squad arrives in Qatar early enough.
"In order for this to happen, the FA would need to look at the fixture calendar, in conjunction with the Premier League, to ensure players can finish the domestic season in very good time.
"England then need to meet up as a team and travel to Qatar at least four weeks in advance to acclimatise to the temperature and play some preparation games."
Webb says Fifa will be taking a close look at reports such as the one conducted by Brewer and his team.
"We're going to be examining various analyses and reports," he said.
"Fifa president Sepp Blatter has indicated he will be bringing it as a discussion point for the Fifa Exco [executive committee] in October so we wait to see the relevant reports. Our biggest concern of course is going to be our players and of course our fans."
Later on Sunday Blatter reportedly told the Associated Press agency he would be "more than surprised if the ExCo will not accept the principle you cannot play in summer in Qatar".
In June the Fifa president said he was determined to switch the 2022 World Cup to the winter because of the intense Qatar summer heat.