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.

In Scottish football, however, Glasgow giants Rangers managing director Stewart Robertson, while insisting he was not criticizing 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."