London (AFP) - The Video Assistant Referee (VAR) should only overturn on-field decisions when there has been a "clear and obvious" error, according to one of football's leading international rules officials.
VAR has proved highly controversial since it was introduced into the Premier League this season.
A particular source of concern has revolved around offside calls.
Last weekend saw Norwich, Brighton, Sheffield United, Wolves, Brighton and Crystal Palace all have goals disallowed by marginal VAR rulings amid doubts over whether the available technology is accurate enough to make such fractional calls.
Players and managers have also questioned whether the system should not be used to reverse an on-field decision that appears correct to the naked eye, a view that received support on Monday from the general secretary of the International Football Association Board (IFAB) -- the sport's ultimate rule-making body.
Lukas Brud, while not addressing specific incidents in English football, said IFAB guidance advises VAR should only be used to correct clear errors also applied to offside.
"Clear and obvious still remains -- it's an important principle," Brud said in comments reported by the British media.
"There should not be a lot of time spent to find something marginal.
"If you spend minutes trying to identify whether it is offside or not, then it's not clear and obvious and the original decision should stand," he added.
Wolves captain Conor Coady was frustrated when his side were denied what seemed a legitimate equaliser just before half-time against runaway league leaders Liverpool on Sunday when Pedro Neto's effort was chalked off because wing-back Jonny was deemed to be offside in the build-up.
Wolves eventually lost 1-0 at Anfield and Coady told the BBC afterwards: "A lot of people are going to tell me that they have come to the right decision and they might have. But what is it, an armpit that's offside, or a toe, or something like that?"
- 'Not helping' -
Meanwhile Sheffield United manager Chris Wilder was annoyed after VAR denied his side a goal against champions Manchester City -- the fifth time it has happened to the Blades this season.
"Yet again we had another goal disallowed by VAR," he said.
"That's about eight or nine over the weekend, this is not a situation helping the game."
Even City manager Pep Guardiola, whose side won 2-0, said VAR was "a big mess", with the former Barcelona and Bayern Munich boss adding: "Hopefully next season it can do better."
But the introduction of VAR into Scottish football cannot come quickly enough for Glasgow giants Rangers.
Sunday saw Steven Gerrard's side win 2-1 away to arch-rivals and reigning champions Celtic as they moved to within two points of the Scottish Premiership leaders.
Gers boss Gerrard's lone criticism of referee Kevin Clancy centred on the official not sending off Celtic defender Christopher Jullien in added time in an incident that saw Rangers striker Alfredo Morelos see red for a second yellow card.
Rangers managing director Stewart Robertson, while insisting he was not criticising referees, said Monday the pace of the modern game made it "extremely difficult to make split-second calls with the degree of certainty required".
He added: "We believe the introduction of VAR would help referees enormously and reduce the number of wrong decisions which sometimes have a dramatic effect on the outcome of matches."