https://www.bbc.com/sport/football/4747 ... nJpvLPqldU
However, Head of Uefa referees Robert Rossetti told the Times in January that - when VAR was introduced into this season's Champions League - officials would penalise any unnatural arm movement that makes contact with the ball.
"The big challenge is the position of the arm. When the arm is totally out of the body above the shoulder it should be penalised. If the defender is making the body bigger in order to block the ball it is not fair.
"It is different if the defender is challenging or playing the ball and it rebounds. But if he is looking to block a cross or a shot on goal and the player is trying to spread his body then it is a handball."
At the weekend, Ifab - football's law-makers - said handball will be given against a player if their arms extend "beyond a natural silhouette" - even if it is accidental.
Ifab chief David Elleray explained: "If the arms are extended beyond that silhouette then the body is being made unnaturally bigger, with the purpose of it being a bigger barrier to the opponent or the ball.
"Players should be allowed to have their arms by their side because it's their natural silhouette."
That new interpretation will come in from 1 June - the date of the Champions League final.