He was speaking ahead of today's start of the European Men's Championships, also being co-hosted by the two nations.

Matches will be held across four venues: consisting of Turin's Tornino Palavela, Busto Arsizio's PalaYamamay, Sofia's Arena Armeec and Varna's Palace of Culture and Sports.

A final is scheduled for the Bulgarian capital Sofia on October 18.

It can be expected that the biennial tournament, which follows the conclusion of a women's event in Belgium and The Netherlands earlier this month, will be a major test for the two nations to showcase their potential.

"The next World Championships will probably, 90 per cent, be in two European countries, different countries," Graça told insidethegames during the FIVB World Tour Finals in Fort Lauderdale.

"Everything is so expensive, that we have to split it between two or three countries.

"The most important thing is we can not afford to fall down a level [following the successful 2014 Championships in Poland].

"We have to work out how to do something similar to this."

FIVB general director Fabio Azevedo also confirmed that "Italy/Bulgaria is the strong candidature we have until now for Men's World Champs and this decision will be taken at the end of this year essentially after the FIVB Executive Committee [meeting] to be held in December".

That decision would then be rubber-stamped at the body's World Congress in Argentinian capital Buenos Aires next year.

The last three editions of the Men's European Championships have been co-hosted, with events having taken place in Austria and Czech Republic in 2011, and in Denmark and Poland in 2013.

But there has never been a co-hosted World Championships until now, either on the male or female sides, with events usually shared around several cities in one nation.

Bulgaria and Italy do not share a border, with Turin and Sofia lying 800 miles apart across the Adriatic Sea and the Balkans.

Graça, who last week unveiled nine new strategic goals designed to propel forward his sport, claims to be "completely open for new ideas".

He has also mooted the possibility of events being shared across up to four nations, with this a possibility for the 2017 Beach World Championships.

Three unnamed candidates have so far expressed interest, he revealed, following on from this summer's event in The Netherlands.

Japan has already been confirmed as host for the next edition of the Women's World Championships, scheduled for 2018.

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