David Beckham and Prime Minister Tony Blair in Singapore on Tuesday. (AP)

Singapore: Paris, favourite to host the 2012 Olympic Games, was under increasing pressure on Tuesday as International Olympic Committee president Jacques Rogge opened a four-day session with two major divisive issues at stake.

Rogge told IOC members they had a tough decision to make Wednesday when they choose the 2012 hosts from five major world city candidates ? London, Madrid, Moscow, New York and Paris ? in the most closely fought bid contest in Olympic history.

“The election... will not be easy in view of the very high quality of the candidates,” Rogge told members as he opened the IOC’s 117th Session at Singapore’s Esplanade performing arts centre. “Four cities will, of course, be deeply disappointed but they should know that a candidature, even if it is not selected, leaves a tangible legacy.”

Before the session closes on Saturday, the IOC will also have to decide which of the 28 sports, if any, it will drop from the Olympic programme and which sports would be introduced instead.

Earlier Tuesday, French President Jacques Chirac arrived to boost Paris’ apparently faltering bid to stage the 2012 Olympic Games.

Paris is regarded as favourite, but faces a growing challenge from London and a potential threat too from Madrid and New York.

Chirac arrived in the city state two days after British Prime Minister Tony Blair landed to promote London’s bid with IOC members. “I have come here to support one candidacy,” the French President said. “We are in the Olympic world ? that means fair play, that means that the best should win and that is what I want. And naturally I want the best to be Paris.”

Unlike Blair, Chirac has not been meeting individual members but he will take part in the presentation of Paris’ bid to the IOC on Wednesday. Blair was flying home on Tuesday to host the G8 summit in Gleneagles, Scotland, where Chirac will join him after the result of the vote has been announced. The decision is expected shortly after 7:30 pm local time.

Rogge has described the vote as too close to call and his view has found a strong echo among members and candidate delegations with few ready to make a confident prediction.

New York, whose chances appeared to have been blown last month when they had to make a late switch to their main stadium venue, seemed to have bounced back confidently.

They flew in Senator Hillary Clinton, the former First Lady, and boxing icon Muhammad Ali, to join mayor Michael Bloomberg in wooing the IOC and the media Tuesday.

Ali appeared alongside Bloomberg, who described him as a true Olympic champion. “He was a gold medal winner and a true hero to an awful lot of us,” he said.

Moscow, regarded as the only real outsiders in the vote, announced that President Vladimir Putin would appear in a video during its presentation and that he would speak in English publicly for the first time.