The 2012 London Olympics Organising Committee has confirmed energy company EDF as a major sponsor for the Games.
Lord Coe said he hopes the Games will deliver a lasting legacy
The company joins Lloyds TSB as the second major corporate partner to back London 2012.
The sponsorship deal gives EDF exclusive marketing rights in the utility services sector, including use of the new London 2012 logo.
EDF Energy was the first company to sign up as a premier partner for the bid in 2004.
Games chairman Lord Coe said he was "delighted" by the move.
"This is very important to us: sustainability is at the heart of London 2012 and we're looking forward to working with EDF to make London a 2012 truly sustainable Games."
The deal, which comes into effect immediately, also gives EDF exclusive access and marketing rights to Team GB and Paralympic GB for Beijing 2008 and Vancouver 2010.
Pierre Gadonneix, company chairman and chief executive, said EDF Energy would use their association with the London Olympics to encourage people to make a 15% improvement to their carbon footprint by 2012.
"I am delighted that EDF will be an official partner of London 2012," he said.
"This deal is a valuable investment in the international development of our brands in our key markets. It will help inspire our customers and our employees across the EDF group."
EDF has an ongoing partnership with the French Olympic Committee and is patron of the International Paralympic Committee.