The game's showpiece is traditionally held in the northern hemisphere's summer but the stifling heat in the Middle East at that time of year has led to calls for a rethink.

And Blatter, speaking at the launch of the Asian Cup in Doha, told reporters: "I expect it will be held in the winter.

"We have time to look at this question, it is still 11 years away but we must decide the most adequate period for a successful World Cup which means January or the end of the year."

FIFA's executive committee opted to take the World Cup to Qatar, ahead of more favoured nations Australia and the United States, in December, having also decided to stage the 2018 tournament in Russia.

Concerns regarding the conditions were initially tempered by the promise of air-conditioned stadiums and training venues but Blatter now believes FIFA could change tack for the well-being of the players.

He added: "Do not forget there is still 11 years to go and although we have the basic conditions of their bid for a June and July World Cup, the FIFA executive committee is entitled to change anything that was in the bid.

"When you play football you have to protect the main people, the players."

Any change to the world calendar would play havoc with domestic schedules, especially in Europe where the majority of leagues play through the winter.

Blatter has denied previously that FIFA were motivated by money in taking the tournament to Qatar.

He said last month: "If we wanted to make money, we would have gone to the United States and not this country.

"I understand that it may seem surprising, but we must not forget that they are making efforts and they have already hosted FIFA competitions."

He continued: "With Qatar, we are opening football to a new world and a new culture.

"The Arab world has tried several times, with Morocco and Egypt for example, to host the World Cup."

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Arsenal manager Arsene Wenger, who had supported England's failed 2018 bid, said the the entire football programme around the world would have to change to accommodate a winter World Cup.

"It looks like an idea that has come out of nowhere because nobody was told that when the bid was voted for," he said.

"That is a bit of a surprise and certainly it would mean that the whole world of football has to be reorganised.

"As you know we have a Christmas period which is quite busy here and England would be very happy to play the World Cup in January just after that.

"It would demand a complete reorganisation of the whole world's fixtures and I cannot see that happening.

Wenger believes the proposals are a recipe for confrontation.

"Certainly it would create many problems, yes, between clubs and countries and countries and FIFA," he said.

Sunderland boss Steve Bruce said: "What are we going to do with our league?

"I can't get my head around that. What are you going to do with all the leagues around the world?"

Fulham manager Mark Hughes said the logistics of re-organising world football would be difficult.

He added: "There must have been some thought gone into it or they would not have awarded the World Cup to Qatar in the first place."

Asked whether it meant the Premier League would still be playing matches in July he added: "That's the only way round it from my interpretation. It's going to be a huge change that year and how it impacts we won't know until it actually happens."

Everton boss David Moyes said: "First of all I would ask was everyone aware of that before they made their choice?

"Because I think if that had been put to the relevant countries there may have been a lot of people not choosing Qatar.

"If that wasn't done, it's not correct. He's not given people the right information.

"Obviously we have to respect the other countries. If that is the best time to play football then we have to do it.

"How long would the Premier League have to break for?

"Before the last World Cup they wanted six to eight weeks' preparation with the players before they went, then you had the World Cup, then the players needed a break when they came back. A lot of them still haven't recovered.

"You might have to rule a good part of that out. It makes it very difficult for the level of football we play in this country."

Harry Redknapp sarcastically said the idea was "another clever move from Mr Blatter".

West Ham manager Avram Grant said: "They needed to think about this before. I think it is not a bad idea. I am pleased there is a World Cup in Qatar. Sometimes you need to give the opportunity to host it to others if they can do it."

The Israeli added: "When you play in hot countries in the summer it is very difficult to play so it is not a bad idea.

"But I like it when ideas come before decisions not after decisions."

Aston Villa boss Gerard Houllier said: "This will be 11 years away. God knows what will happen in 11 years in terms of progress and everything.

"But I would not be surprised if the World Cup is played in January because you can't play in the summer period in Qatar."