Reports in the British media on Sunday claimed Mohamed Bin Hammam, former president of the Asian Football Confederation (AFC), paid up to $5 million to football officials to drum up support for Qatar's bid.
Bin Hammam had previously been a member of FIFA's executive committee, but was banned for life from all football activity in December 2012 following allegations of bribery.
"The Qatar 2022 Bid Committee always upheld the highest standard of ethics and integrity in its successul bid to host the 2022 FIFA World Cup," the statement read.
"In regard to the latest allegations from The Sunday Times, we say again that Mohamed Bin Hammam played no official or unofficial role in Qatar's 2022 Bid Committee. As was the case with every other member of FIFA's Executive Committee, our bid team had to convince Mr Bin Hammam of the merits of our bid."
The committee also revealed it was co-operating with an on-going investigation, which is being led by former United States attorney Michael Garcia, who heads the investigatory chamber of FIFA's ethics committee.
The statement added: "We are co-operating fully with Mr Garcia's on-going investigation and remain totally confident that any objective enquiry (sic) will conclude we won the bid to host the 2022 FIFA World Cup fairly.
"Following today's newspaper articles, we vehemently deny all allegations of wrong-doing. We will take whatever steps are necessary to defend the integrity of Qatar's bid and our lawyers are looking into this matter.
"The right to host the tournament was won because it was the best bid and because it is time for the Middle East to host its first FIFA World Cup."
Sunday's statement contradicts previous comments from Qatar 2022 bid chairman Sheikh Mohammed bin Hamad bin Khalifa Al Thani in 2010, which saw him label Bin Hammam as the bid's "biggest asset".
The allegations are the latest to blight Qatar's bid, after accusations that ex-FIFA vice president Jack Warner had received $2million from a firm controlled by a former Qatari football official.
