UEFA will introduce thicker lines for offside decisions reviewed in the Champions League and Europa League by Video Assistant Referees [VARs], in a bid to encourage more goals from next season.
The new lines, which may yet be used in this summer's European Championships, can be used under the existing laws of football.
UEFA president Aleksander Ceferin says he has been in talks with the organisation's refereeing officials to roll out the changes to ensure sides are not "ruined" by one wrong decision.
"One centimetre offside is not offside," said Ceferin, in an exclusive interview with Sky Sports News. "Because that's not the meaning of the rule. And it has to be clear and obvious mistake for VAR to intervene.
"So, thicker lines are essential because the line is drawn subjectively. So, it's not exact and if one centimetre… you ruin the season of a club with one wrong decision. And, for me, the handball is also problematic, but I don't know what exactly to do about it. We are discussing a lot with our referee officers."
Football lawmakers, the International Football Association Board [IFAB], allow competitions to determine the level of accuracy of their VAR systems, with no specific law about the width of offside lines.
The Premier League will discuss its use of VAR, including offside decisions, at a club meeting next month.
UEFA: Agreement 'very close' over Champions League reforms
Ceferin has confirmed that an agreement between European clubs is "very close" over proposed changes to the Champions League format, following talks before UEFA Congress in Amsterdam this week.
UEFA's president met Premier League chief executive Richard Masters, alongside top officials from the five largest leagues in European football, during a meeting on Monday.
The talks, involving UEFA and the European Leagues, were organised by European football's governing body.
"We understand that the European ecosystem is very much connected," said Ceferin. "We have to stick together. We have to discuss the future of European football. We will all have to step back a while.
"But, at the end, the decision will be made by the Executive Committee of UEFA. With a lot of discussion, I think we will agree very soon because we know what the principles are, all the leagues and 95% of the clubs knows what the principles of European sports model and, especially football is."
The European Club Association [ECA] holds its 24th General Assembly in Budapest on 30/31 March.