The 77-year-old revealed that every Fifa member state will have a vote to choose the hosts of the world's biggest international tournament
The awarding of 2018 and 2022 tournaments to Russia and Qatar respectively saw the governing body criticised heavily, and the 77-year-old admitted that the presence of politicians influenced the decisions.
"The selection of a country to host the World Cup or the Olympics is something that inevitably is of great interest to the governments of the candidate nations," he told AS.
"I can understand that the political leaders try to convince other countries to vote for them - I saw this in December 2010, when Russia was chosen for 2018 and Qatar for 2022. But I have seen it ever since I began working for Fifa more than 38 years ago.
"Future World Cups will no longer be decided by a vote of the 25 members of the Executive Committee, but will be chosen by the 209 presidents of each Fifa federation. The Executive Committee will serve only to create a final shortlist of a maximum of three candidates to host the competition.
"[Choosing two hosts at once] was a mistake. Two World Cup hosts will never again be chosen in one day. That was an error from a political point of view, although in terms of marketing and television it wasn't."
Blatter revealed that the 2022 World Cup is still set to be played in summer, with the hosts yet to apply to move the competition amongst worries about the high temperatures in the Middle East.
"It's quite simple. The Qatar World Cup was chosen to be played between the months of June and July. For that to change and for the competition to be played in winter, it's necessary for the host nation, Qatar, to request this. And they still haven't.
"They know that if they do, and in doing so they will affect the basic conditions of the World Cup, they risk another of the 2022 candidates complaining to Fifa and the vote being re-run. The selection of Qatar was a surprise for the whole world."
Uefa president Michel Platini has announced plans to play Euro 2020 across the continent, with no main host nation, but Blatter feels this was a mistake.
He added: "I believe it should be one event, one country. It is a mistake to hold a World Cup in two different countries. We did this in 2002 in South Korea and Japan, and it won't happen again. You lose identity and passion."