Sebastian Coe has been appointed as a non-executive board member of England's 2018 World Cup bid team.
Lord Coe will continue to chair the London Organising Committee for the 2012 Olympic and Paralympic Games.
But he has agreed a leave of absence from his position as chairman of Fifa's ethics committee.
"Winning the World Cup would be the hat-trick in a golden era for the UK following the Olympics in 2012 and the Commonwealth Games in 2014," said Coe.
It is understood that Coe, who led the team that successfully secured the Olympics and Paralympics for London, will not receive a salary for his position with the 2018 bid.
"I look forward to playing my part in our bid for the Fifa World Cup," he added.
"I am passionate about football so am delighted to be standing alongside many other people and football greats up and down the country in bidding for this event.
"I would like to thank Fifa President Mr Blatter for agreeing to this arrangement."
England 2018 Ltd chairman Lord Triesman said: "I firmly believe that making Lord Coe a member of our executive board significantly enhances our chances of success.
"Lord Coe is a highly regarded international sports ambassador who is not only passionate about football but also commands great respect in the global football community.
"His experiences in leading the successful London 2012 Olympic and Paralympic bid and generating a wealth of domestic and international support will be invaluable to us.
"He is also held in high esteem by the Fifa football family and this, coupled with his London 2012 success, means he is a tremendous addition to the board and to the 2018 team in general."
Lord Coe joins Sir Keith Mills, another member of the London 2012 bid, as a non-executive director of the World Cup bid team.
