Image source, Getty Images Image caption, England had been set to take on Mexico at the Azteca at 6pm local time
England's World Cup last-16 tie with Mexico is set to be moved to 19:00 BST on Sunday.
Fifa is understood to be locked in talks over the scheduling of the game at Azteca, Mexico City, which had been due to kick off at 01:00 BST on Monday (18:00 local time on Sunday).
Forecasts suggest there could be thunderstorms and heavy rain around that time, though Fifa is yet to provide any explanation for the change.
Under tournament safety rules, any lightning strikes detected within eight miles of the stadium result in an automatic 30-minute delay to play.
Fifa regulations for World Cup 2026 state it has the right to "cancel, reschedule or relocate" matches "at its sole discretion".
Football's world governing body maintains no decision has been made on rescheduling the fixture, and it remains in talks.
The Football Association (FA) had been planning as normal on Friday for Sunday's game, with officials involved in planning and security discussions.
Sources have told BBC Sport suggestions of a change, which was first reported by local media in Mexico, took the FA and its Mexican counterparts by surprise.
The match will be broadcast live on BBC TV, BBC iPlayer, BBC Radio 5 Live and the BBC Sport website and app.
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Published 1 day ago 'Not ideal but it doesn't really matter' Asked at England's training session on Friday about the possibility of the game being moved, winger Marcus Rashford said it was "not ideal" but the squad would deal with it.
"I think for us it's the same how we prepare for the game," he said. "It has to be the same.
"We have to be focused. We have to be ready for anything. I think it's one of our strengths as a group.
"Everyone, including the players and staff... we are ready for whatever challenges get thrown at us. So obviously it's not ideal but also it doesn't really matter."
The build-up to Sunday's fixture has been dominated by talk about Mexico's record at the Estadio Azteca and how England's players will deal with the altitude.
The arena sits 7,220ft (2,240m) above sea level, and Mexico have lost just twice in 89 matches at the iconic stadium.
At that altitude, the Earth's barometric pressure is lower, making the air thinner and meaning less oxygen is taken into the bloodstream with each breath.
Even for professional footballers, that has a potentially significant impact - increased heart rate, shortness of breath, dehydration, quicker and more intense fatigue.
The fixture had been set to start in the early evening, when temperatures were forecast to be about 20C.
However, a midday kick-off is expected to see temperatures hit highs of about 26C, which will theoretically make conditions even more difficult.
France's group-stage fixture against Iraq was delayed for over two hours because of safety concerns amid adverse weather conditions in Philadelphia.
Last summer's Club World Cup, which was also hosted by the United States, had six major weather delays across the 63 matches played.
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While most fans in England are likely to welcome an earlier kick-off time, the timing of Fifa's decision could prove disruptive to supporters attending the match.
More than 3,000 England supporters are set to attend the fixture at the Azteca, which holds 87,000.
Plans that had been finalised weeks - or even months - in advance will now have to be changed to ensure they can make the match.
But plans at home had been altered to, with Prime Minister Sir Keir Starmer announcing on Thursday that emergency legislation had been passed to allow pubs in England and Wales to open until 5am on Monday.
England manager Thomas Tuchel had urged parents to allow their children to watch the match in the early hours of Monday, and to "write an excuse for school" the next day.
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Sources: BBC Sport · Sky Sports
