The governing body said there were "slight inconsistencies" in the way that referees from around the world interpreted different rules.

As a result, the Committee has now published clarifications to inform players, coaches, referees and spectators of exactly how the rules are intended.

Ahead of the Paralympic Games in Rio de Janeiro next month, these have been re-published to ensure athletes are fully aware of how the rules will be enforced.

This news comes after BISFed wrote a letter to all manufacturers of boccia balls, inviting them to participate in the second stage of an enquiry into current testing processes.

In the letter, BISFed claimed that the existing tests "do not provide guarantees" that all balls used in tournaments allow for a fair competition.

At BISFed’s General Assembly in 2014, a motion was passed authorising the governing body to find a solution to the problem.

BISFed therefore tasked Loughborough University to conduct a two-stage research project and to advise on a solution.

In stage one, the University recommended that BISFed should introduce a new test - the "roll" test - which determines the minimum distance a boccia ball must be capable of rolling in order to be accepted for competition play.

The letter invites manufacturers to participate in stage two - the design of the new roll test - by submitting a set of boccia balls.