Obama has written to members of the IOC to reassure them that Chicago's bid has his full backing, even though he may not be in Copenhagen next week for the final vote.

Obama's letter promised that the United States would "welcome the world with open arms" if Chicago is selected.

He wrote: "The City of Chicago is designed to host global celebrations and it will deliver a spectacular Olympic experience for one and all."

The 338-word typed form letter, dated September 10, is addressed to individual members and bears the signature of the President.

He wrote: "I deeply appreciate the tremendous work of the Olympic Movement and wish to convey my strong support for Chicago 2016."

The White House has noticeably stepped up its efforts in recent days as the vote at the IOC Session in the Danish capital on October 2 approaches.

Earlier this week former British Prime Minister Tony Blair, who helped London win its bid to host the 2012 Olympics, met privately in New York with Obama's senior adviser on the Olympics, Valerie Jarrett, a White House official said.
 

Blair and Jarrett discussed strategy about the Olympic host-city election process and gave her advice on how to handle the "home stretch" of Chicago's Olympic bid, the official said.

The one-on-one meeting lasted for an hour.

It is also still unclear whether Hatoyama will be part of Tokyo's delegation in Copenhagen but his letter to IOC members assures them that Government support for their bid "remains as strong as ever".

Hatoyama, who took office last week after his Democratic Party defeated the long-ruling Liberal Democratic Party in elections at the end of August, wrote: "Japan has undergone a change of national Government.

"However, I would like to offer you my fullest assurance that Japan's commitment to the Olympic Movement and to Tokyo's bid to host the 2016 Olympic and Paralympic Games remains as strong as ever."

King Juan Carlos, who will be part of Madrid's delegation in Copenhagen, has also written to IOC members.

The King, who entertained the IOC Evaluation Commission led by Morocco's Nawal El Moutawakel at the Royal Palace during their visit to Madrid in May (pictured), noted in his letter that he competed, in sailing, at the 1972 Munich Games and that several other members of the royal family have also been Olympians.

He wrote: "In 2016 Madrid aspires to organise Olympic and Paralympic Games that will leave an enduring legacy for the Olympic Movement.

"We all strongly believe that Madrid represents the best option at this time.

"Madrid is a great capital, which has multicultural traditions and a long, rich history.

"The city, thanks to the Games, will show itself to the world as an example for future generations of peaceful coexistence and integration."

Lula, who has campaigned tirelessly on behalf of Rio, had written to the IOC members in July to tell them that he would definitely be in Copenhagen for the Session.

He wrote: "We Brazilians understand the tremendous power of sport to transform nations and touch the lives of millions of people, especially young people.

"We also appreciate that no-one has done more, over many years, to harness that power than you in the Olympic Movement.

"For Rio de Janeiro to host the Olympic and Paralympic Games in 2016 would not only be a great honour, but also provide a wonderful catalyst for the ongoing social transformation of our country and our continent.
"We believe that the Olympic Flame will burn even more brightly in Rio."

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