London - Major sponsors Adidas and Sony have on Sunday demanded that FIFA carry out a thorough investigation of corruption allegations over Qatar's 2022 World Cup-bid stepping up pressure on football's governing body to act.
The two companies, between them, account for hundreds of millions of dollars of sponsorship for FIFA.
Adidas said in a statement emailed to AFP that it was "confident that the matter is being dealt with as a priority".
The company said it had a "long-term and successful partnership with FIFA" that it looked forward to continuing.
"Having said that, the negative tenor of the public debate around FIFA at the moment is neither good for football nor for FIFA and its partners," Adidas said.
Sony was reported by The Sunday Times as saying that it wanted FIFA to hold an "appropriate" investigation into the Qatar allegations.
"As a FIFA partner, we expect these allegations to be investigated appropriately," the Japanese electronics giant told the paper.
"We continue to expect FIFA to adhere to its principles of integrity, ethics and fair play across all aspects of its operations."
Contacted by AFP in Tokyo, Sony spokesman George Boyd said: "We decline to comment on details of our communication with FIFA."
Former US federal prosecutor Michael Garcia is leading a FIFA investigation into controversies surrounding the vote for the 2018 and 2022 World Cups.
Garcia has said he will conclude his investigation by June 9, but is not expected to submit his final report until mid-July.
Allegations of skullduggery have surrounded Qatar's bid ever since its shock victory at a FIFA vote in Zurich four years ago.
The tiny Gulf state prevailed over the United States, Australia and Japan, despite a FIFA technical report which warned the searing temperatures in the region during June and July posed a health risk.
The Qatar 2022 Supreme Committee for Delivery and Legacy insists that it won the bid "on its merits."
It has also said bin Hammam played no "official or unofficial role" in the bid committee.
The new accusations against Qatar have come from the British newspaper, The Sunday Times, which this week detailed bin Hammam's meeting with key officials ahead of the FIFA vote.
The paper alleged bin Hammam was invited to visit Russia's then prime minister Vladimir Putin to discuss "bilateral relations in sport" in October 2010.
It also said bin Hammam helped arrange talks on a major gas deal between Thailand and Qatar during a visit to Doha by the president of the Football Association of Thailand, Worawi Makudi.
Bin Hammam was on FIFA's executive committee but resigned in 2012, shortly before being banned for life from football administration by FIFA's ethics committee.
Meanwhile, Argentine football legend Diego Maradona joined the chorus of criticism against FIFA.
"There are huge bribes" in the world football governing body, Maradona, now based in the United Arab Emirates, told Abu Dhabi daily, Al-Ittihad.
"Those behind them must be held accountable, especially in regards to the latest events related to awarding Qatar the 2022 World Cup.
"Where has this money gone, who received it, and why," must be investigated, he said, adding that he had repeatedly denounced, "in vain, cases of bribery within FIFA."
Maradona also criticized UEFA president Michel Platini, who voted for Qatar's bid.
"It is unfortunate that there are footballers within FIFA such as (UEFA
president Michel) Platini, who have surrendered" to such irregularities, he said.
Platini has attacked British media for seeking to "tarnish" his reputation by drawing him into the corruption claims.
The former French international has said a re-vote for the 2022 World Cup should be held if corruption allegations are proven.