London - The high and mighty accustomed to motorcades with dozens of well-armed security guards are being forced to travel light at the Olympics.Organizers are limiting some leaders to one or two security guards inside the Olympic Park, depending on the dangers they're deemed to face. Their bodyguards can't sit with them; they'll have to stand in the back. And some VIPs will even have to forgo their stylish rides and travel together - on a humble bus.Gilbert Felli, executive director of the International Olympic Committee, conceded that efforts to keep the huge security operation as low-key as possible are rankling some VIPs."It is always an issue, at every Olympic Games," he said.While that's true, other Olympic games haven't drawn the same number of A-list dignitaries as London. At least 100 heads of state are expected - compared with 86 who visited the Beijing Olympics in 2008 - as well as 150 other high-profile figures who need protecting, including kings and queens, corporate magnates.US, IsraelBritish police, the Home Office and intelligence agencies have assessed each nation's security requests - including numbers of bodyguards - analysed the risk each dignitary faces, and determined their travel and security arrangements."Some will come all together on a bus, and others with special transportation," Felli said. "It is all according to the risk that Britain will evaluate."Israel and the United States are the delegations with the highest risk, according to Jonathan Evans, director-general of Britain's domestic spy agency MI5, because al-Qaeda and its affiliates are most likely to target them. Other delegations may find themselves with less protection than they would like."A lot of foreign politicians who when they are visiting this country would perhaps normally get protection, wouldn't be part of that this time because resources have been stretched so wide," said Mike O'Neill, chairman of the close protection section of the British Security Industry Association.Delicate discussionsPrime Minister David Cameron acknowledged there have been delicate discussions with other nations on security plans, and that Britain is imposing strict rules."Obviously we work very closely with all the visiting delegations, visiting countries, and have a whole series of rules and protocols in place," he said.Scotland Yard has declined to discuss exactly how many British police will be assigned to VIPs. In all, the Olympics security force is comprised of about 12 500 police officers, 18 200 military troops, 7 000 private security guards and 3 000 volunteers.British authorities insist the risks to dignitaries will be low inside Olympic venues because of the dense layers of protection around them.LayersOnly people with credentials or tickets can enter the Olympic Park's main areas, and only after they have passed through airport-style security screening. In a wide zone around the Olympic Park, officers will scour high-rise buildings and other places that could provide a vantage point for a hostile gunman. Beyond that, missiles and fighter jets are primed to intercept airborne threats.At nearby Canary Wharf, police and diplomats staffing a protocol coordination centre will keep watch on events overseas that could have ramifications for foreign dignitaries. The team has already rehearsed a raft of scenarios, from an Israeli attack on an Iranian nuclear facility, to a coup in a fictional nation.O'Neill said some protection teams will have private jets on standby at airfields across the capital, ready to evacuate high-profile figures in case of a terrorist attack."They would have plans to get them away from the scene of any trouble, to get them out of London - and potentially get them out of the UK completely," he said.