Pentathlon Canada was among those saying it was "caught off guard" in a statement.

"As the decision preceded consultation with National Federations (NFs), it concerns us that the voice of the global community was not concluded," they said.

"We realise that pentathlon needs to innovate to improve accessibility and inclusion for more athletes.

"We remain hopeful that a solution may exist to retain the five core disciplines of pentathlon through reform of the riding rules, point system and education."

The Modern Pentathlon Federation of Sweden called for the UIPM to keep the event in modern pentathlon or the Board to resign as a consequence.

Neighbouring Finnish Fencing and Pentathlon Federation accused the Board of breaching the UIPM statutes and called for a cease and desist of any progress on the decision until details were relayed to NFs.

The Modern Pentathlon Federation of the Republic of Kyrgyzstan said that missing one of the five events of modern pentathlon would "destroy the idea of Pierre de Coubertin" and said its absence would be "a violation of the integrity of this sport".

Pierre de Coubertin was the founder of the International Olympic Committee (IOC), its second President, and the creator of modern pentathlon which debuted at the Stockholm 1912 Olympics.

In Poland, a letter was sent to the Polish Modern Pentathlon Association with 119 signatures from athletes and coaches who were against the move, calling it "unacceptable".

"We are aware of the necessity to introduce changes and standardisation of the rules of holding a horse-riding event during the competition," it read.

"Adapting these rules not only to competitors skills but also to the horses' abilities.

"There are many solutions, the introduction of which will make horse riding in a modern pentathlon safer for both parties."

The Czech Union of Modern Pentathlon also wrote of their disapproval of the change, while Hungarian athletes wrote to IOC President Thomas Bach expressing their disappointment and calling for the resignation of the Board.

A decision was made last week by the UIPM Board to remove riding from the programme stating the IOC would "only accept a proposal without riding" for the Los Angeles 2028 Olympic programme, set to be decided in December.

It comes after controversy in the sport at the Tokyo 2020 Olympics, when German coach Kim Raisner was caught punching the horse Saint-Boy, which later did not jump during the Games when ridden by then-leader of the competition, Germany’s Annika Schleu.

Several horses did not jump at the Games.

Yesterday, the UIPM held a consultation with athletes, with activist group Pentathlon United stating that a lot was still "unclear" following the meeting.