A series of modifications have been made to the refereeing rulebook after the IJF received recommendations from National Federations.

The most contentious change impacts the reverse seoi nage which will no longer be a scoring move and will instead result in a penalty for the judoka.

The move - which was popularised by Olympic champion Choi Min-ho of South Korea - sees judoka grip their opponent before rotating and throwing them onto their back.

IJF referee supervisor Neil Adams has explained the new rules in a 20-minute video but no reason is given for the decision to ban reverse seoi nage.

Many judo fans have taken to social media to voice their frustration and call for clarity over the decision.

Other rule changes include athletes receiving a shido if they retie or adjust their judogi or hair on more than one occasion.

Head diving has been ruled as a dangerous move with the judoka receiving a disqualification from the bout for committing the offence, while athletes will be penalised if two elbows or hands simultaneously touch the floor when falling backwards.

There have also been changes to rules on gripping.

Vladimir Barta, head sport director for the IJF, said the aim of the rules is to protect athletes while "promoting judo to be more dynamic, more attractive for the public and the media".

"We have received proposals and recommendations from National Federations for rule amendments and changes," said Barta.

"The IJF is working hard to modernise our beloved sport with input from partners.

"These new rules will come into force from the beginning of 2022, in place until 2024."

The new rules are set to be introduced at the Odivelas Grand Prix, scheduled to be held from January 28 to 30 in Portugal.