Update: 12:23PM Top European football officials have publicly called on Sepp Blatter to end his reign as FIFA president amid accusations of corruption against Qatar's 2022 World Cup bid.
Michael van Praag, head of the Dutch football association, said Blatter should quit when his term ends next year. A similar demand was made by David Gill, vice-chairman of England's Football Association,
Blatter, 78, officially opened FIFA's annual congress at a gala evening in Sao Paulo without mentioning the attacks or corruption controversy. He is expected to use the congress to announce on Wednesday that he will seek a new four year term.
"Tonight we are in a festive mood because let's say the discussions and all of what's linked with FIFA and is so important nowadays, we will discuss it tomorrow," Blatter said.
"What is uniting us today and tomorrow and in the next month is the love of this beautiful game.
"They (fans) want to be here, they want to live this fiesta," the FIFA boss said.
The corruption allegations and criticism of Blatter have threatened to further taint the opening of the latest World Cup in Sao Paulo on Thursday. Brazil is already struggling with protests over the cost of the event.
Van Praag challenged Blatter when he appeared before a closed meeting of the European confederation, UEFA. Some federations are angry because Blatter said in 2011 when he secured his latest term that it would be his last.
"Mr Blatter, this is nothing personal but if you look at FIFA's reputation over the last seven or eight years, it is being linked to all kinds of corruption and all kinds of old boys' networks things," Van Praag said he had told Blatter.
"FIFA has an executive president and you are not making things easy for yourself and I do not think you are the man for the job any longer."
Blatter replied that he would not resign straight away, according to the official.
The English FA's Gill also said it was "disappointing" that Blatter had changed his stance and the FIFA leader should leave next year.
"I think we need a full, frank and open debate about what FIFA needs going forward."
UEFA president Michel Platini has been touted as a possible rival to Blatter when the FIFA vote is held in May next year. Platini has said he will only decide his candidacy in September.
Van Praag said that if Platini does not stand then UEFA should agree another candidate to stand against the Swiss official.
Blatter was given a standing ovation when he spoke before the African, Asian and North American-Caribbean confederations on Monday. "This time, before UEFA, he did not get it," van Praag said.
Blatter has been FIFA's president since 1998. But his rule has never seen a controversy like the accusations that Qatar paid for votes when FIFA chose the Gulf country to host the 2022 World Cup.
Qatar has strongly denied involvement in wrongdoing. But allegations made in British newspaper The Sunday Times are expected to be raised at the FIFA congress.
Blatter hit out at the "storm against FIFA" over Qatar and the "discrimination and racism" at the heart of the attacks when he addressed the African Football Confederation on Tuesday.
African football officials were among those said to have accepted Qatar's money, according to the Sunday Times. CAF members gave Blatter a rousing reception and slammed the allegations in a statement.
Qatar beat the United States, Australia, Japan and South Korea to the 2022 tournament.