Blatter satisfied with outcome of FIFA probe
He also added FIFA would have to toughen up its anti-corruption watch in the future.
"You cannot avoid collusion but if there should be something wrong in such collusion, then naturally somebody should intervene," Blatter told a news conference.
"You find collusion in politics, in elections, when two parties are enemies during the year and then they run together."
Two FIFA executive committee members were banned and fined on Thursday, one for bribery, over allegations they had offered to sell their votes in the contest to host the 2018 and 2022 World Cups.
Four other officials were also banned and fined for various offences including bribery in three cases.
However FIFA's ethics committee, which investigated the case, found no evidence of alleged collusion between Spain/Portugal, one of four bids to host the 2018 World Cup, and Qatar, who are bidding for 2022.
The hosts for both tournaments will be chosen on December 2 in Zurich. Blatter said last month that FIFA had been wrong to decide to vote on both tournaments at the same time.
"The World Cup is not only footballing, emotional competition, where people assemble, they dance, they are happy," he said.
"It (December 2) is not just an important date for football, it is important for international politics.
"We have nine bidding countries for the 2018 and 2022 World Cups, they will send their top representatives, we have to deal with nine countries sending prime ministers, heads of state and other high-ranked political personalities."
A FIFA committee has compiled detailed reports on each of the nine bids but there has also been intense lobbying behind the scenes of the 22 executive committee members who can vote.
Asked if he thought the quality of the bids would be decisive, Blatter said: "In principle, yes, otherwise it wouldn't be worth making a technical report if finally those who are going to vote are not using the information of such reports.
"But we are not only dealing with the World Cup institution, we are also dealing with human beings and they have ideas other than those which are available in the documents."
Blatter said he was satisfied, but not happy, about the outcome of the ethics committee hearing.
The investigation started when executive committee members Amos Adamu of Nigeria and Reynald Temarii of Tahiti were accused of offering to sell their votes to undercover reporters from the Sunday Times British newspaper posing as lobbyists for an American consortium.
"It gave us the opportunity to clean a little bit whatever has to be cleaned but I cannot say it is very fair when you open traps for people," said Blatter.
"I am very satisfied, but I'm not happy, you cannot be happy when you have to sanction members of our family, it is not a pleasure but I'm satisfied with the work down by the ethics committee.
"It is with optimism that I'm looking forward to the last few days before the decision day of December 2," he added. "I am convinced that between now and December 2 there will be no more cases."
Blatter also said FIFA would have to toughen up procedures in the future.