Proposed amendments to the offside law represent "an absolutely huge change to the game at every level" according to Football Association chief executive Mark Bullingham.
The game's law-making body the International Football Association Board decided at its annual general meeting on Saturday to look at how the law could be changed "to foster the spirit of attacking play".
There have been a number of goals disallowed for offside following VAR reviews in the Premier League this season which have been extremely marginal, which have led for calls for the law to be looked at.
IFAB has responded by tasking its football and technical advisory panels with coming up with suggestions for how the law could be changed. Trials of the amended law could come into effect as early as the 2021-22 season if given the go-ahead at next year's AGM in Wales.
FIFA president Gianni Infantino appears to favour the principle that there should be 'daylight' between the defender and attacker, and Bullingham concedes that would mean a fundamental shift in the game.
"It will be an absolutely huge change to the game at every level, there's no question of that," he said.
"Our main reaction for that was that nothing was rushed, it was thought through, and now we've got a year to develop protocols, what they could look like.
"There will inevitably be unforeseen consequences, but if you come back to the basic philosophy that we want to encourage more attacking football, which we do, then it's something worth exploring."
The Premier League's decision to use pitchside monitors sparingly for subjective reviews was questioned by IFAB's technical director David Elleray, who said he would be "astonished" if the league did not change its policy for next season.
Bullingham said: "The Premier League is in its first year with VAR and they are adapting their protocol all the time.
"We do expect to see them use the monitor more, they have given that indication anyway, so we see that as a non-issue really."