Italy will hope to defend their U19 boys' volleyball world title in Tehran ©Getty Images

Eighteen teams are set to compete in the 17th edition of the International Volleyball Federation (FIVB) Boys' Under-19 (U19) World Championship in Tehran, with Italy hoping to defend the title they won in Tunis two years ago.

The biennial competition was established in 1989, with Tehran last hosting in 1997, as Italy won their first of two titles on that occasion.

The Italians will now look to add a third crown, after defeating Russia 26-24, 21-25, 25-19, 25-18 in the 2019 final.

Hosts Iran, who are third in the all-time medal table behind Brazil and Russia, including their time as the Soviet Union, will push Italy hard.

They won the event in 2017, also defeating Russia in the final in four sets.

Brazil are the most decorated team in the competition but have not won the title since 2003.

Another challenger for the title will be Russia, who have finished second in the last two U19 World Championships but missed the U19 European Championship due to COVID-19 restrictions.

The Dominican Republic and Guatemala withdrew from the initial 20-team field.

They have forfeited all their matches and will finish joint-19th.

The tournament consists of two pools of four and two pools of five, with the top two from each advancing to the quarter-finals.

Due to coronavirus restrictions, the Championship will be held without spectators. 

All matches will be streamed live on the Volleyball World YouTube channel.