The International Volleyball Federation (FIVB) has decided to increase the number of teams participating in the men's and women's World Championships to 32.
The expansion, approved by the FIVB's Board of Administration, will allow eight more teams to compete in each of the two tournaments.
"The FIVB is keen to provide more opportunities for the teams to participate in our main event, the World Championships, while offering the great volleyball spectacles to fans from all over the world to follow," said FIVB President Ary S. Graca.
"The increase in the number of teams participating in the tournament will also offer more opportunities for the teams that are part of the revolutionary program of Volleyball Empowerment that aims to increase the level of teams all over the world to participate in the major volleyball events."
Under a new system that will come into force next year, 32 teams will be divided into eight groups of four in the round-robin phase, with the best two advancing to the knockout rounds.
The previous format saw the top two from each of the six groups advance, along with the four best third-placed teams.
The announcement came on the same day as the conclusion of the Women's World Championship in Poland and the Netherlands, where Serbia successfully defended their title.
Last month, Italy captured the men's world title for a fourth time.