The ICC has decided to add two additional teams but will cut the overall length of the tournament by almost two weeks following criticism of the length of this year's event in South Africa.
There will be four first round groups, with the top two from each progressing to a new Super 8 second round format.
The next World Cup in 2007 is due to be staged in the West Indies, although there is a feeling that some matches could take place in the US.
Explaining the increased number of teams, ICC president Mani stated: "It's a globalisation of the sport. An impressive performance by associate members has prompted us to include more teams."
The International Cricket Council president Ehsan Mani has confirmed that the 2007 Cricket World Cup is to be expanded by two teams to 16 competing nations.
