FIFA President Sepp Blatter delivers an opening speech at the 65th FIFA Congress in Zurich, Switzerland, May 29, 2015. The embattled head of world soccer, FIFA President Sepp Blatter, is expected to be re-elected on Friday despite growing calls for his resignation amid a corruption scandal that has engulfed the sport's governing body. [Photo/Agencies]

ZURICH - World soccer boss Sepp Blatter was expected to be re-elected on Friday, defying growing calls for him to step down in the face of corruption scandals engulfing the sport's governing body.

Addressing FIFA delegates at the body's annual Congress in Switzerland, where members will later vote to decide the organisation's presidency, Blatter promised more transparency and urged members to remain unified.

He also said that FIFA would probably not be facing its present problems if Russia and Qatar had not been awarded the 2018 and 2022 World Cups, respectively.

"Today, I am appealing to unity and team spirit so we can move forward together," he said, in a low key-address that contrasted with his more defiant reaction on Thursday.

Blatter also sought to distance himself from the scandal, the biggest crisis FIFA has faced in its 111-year history.

U.S. authorities have accused top FIFA figures and sports executives of corruption, while Switzerland is separately investigating the award of the next World Cup finals to Russia and Qatar.

"We cannot watch everyone all the time. We have 1.6 billion people directly or indirectly touched by our game," Blatter said.

He recalled that the Russian and Qatar awards were announced together in 2010 and "if two other countries had emerged from the envelope I don't think we would have these problems today".

His opening address was briefly interrupted by a female protester waving a Palestinian flag and shouting at Blatter before being removed. The Palestinians are seeking to have Israel suspended from FIFA at the Congress.

Blatter, who has been heavily criticised for not doing enough to combat corruption in FIFA, is being challenged by Jordanian Prince Ali bin Al Hussein for the most powerful job in soccer.

Infographics show FIFA's voting blocs. [Sources/Agencies]

Anger within Europe's powerful regional soccer body UEFA and other members over the damage allegations of bribery and corruption are doing to FIFA is unlikely to be enough to topple the 79-year-old Swiss, who is backed by the Asian and African confederations and many Latin American states.

English Football Association chairman Greg Dyke said England would support a possible boycott of the 2018 World Cup if Blatter was re-elected president of FIFA.

But the numbers appear to be in Blatter's favour, despite some countries saying they were switching allegiance and predicting that the scandal would finish Blatter as FIFA chief.

Most of the developing world in Africa, Asia and parts of Central America and the Caribbean are reluctant to vote for change in FIFA leadership given that the organization guarantees them annual grants and bonus payments in World Cup years.

Kuwait's Sheikh Ahmad Al-Fahad Al-Sabah, one of the most powerful men in world sport, said Blatter is the right man for the job and should be re-elected.

"FIFA should have a leader with a lot of experience," the FIFA executive committee member told Reuters at Zurich's Baur au Lac hotel, where seven FIFA executives were arrested on Wednesday.

On Friday, New Zealand Football said it would vote for 39-year-old Prince Ali despite a previous unanimous commitment from countries in the Oceania Football Confederation in January to back Blatter. Canada also said it would not support Blatter.