Alain Courtois was director of the Belgian half of Euro 2000 which his country co-hosted with the Netherlands.
He said at the launch of Belgium's part of the triple bid with Luxembourg and the Netherlands that it was definitely "not a joint bid" which are no longer favoured by FIFA.
"We are one entity, one political entity with a common economic base," Courtois said.
FIFA move to clear way for England bid
"Benelux has its own parliament which has existed for 50 years."
He said they were confident of convincing FIFA president Sepp Blatter of awarding the finals to Benelux, even though Blatter has said FIFA is not in favour of future joint bids for football's showpiece event.
Only one of the 18 World Cups staged since the tournament began in 1930 has been split between two countries -- the 2002 finals in South Korea and Japan.
With the 2010 finals in South Africa and the 2014 finals probably set for Brazil, the destination of the 2018 finals is far from certain as FIFA have not yet fixed their continental rotational policy that far into the future.
Blatter has said the 2018 event could be held in North America, but a number of countries around the world are also considering bidding with England, Russia, the United States, China, Italy, Spain and Australia all possible contenders.
Courtois confirmed that both Belgium and Luxembourg had given their political backing to the bid with the Dutch expected to follow suit next week when the Dutch FA meets its government.
He said: "In 2000 we were the first European Championships to make a profit and the fact that we are one of the most wealthy, accessible and highly populated regions of the world means we are a perfect choice.
"But you must also look at the recent awarding of the European Championships to Austria-Switzerland in 2008 and Poland-Ukraine in 2012 to see that joint bids can also be successful too."
- REUTERS -
Sven lost sleep over World Cup
FIFA confirm Brazil sole 2014 bidders