The flame is due to arrive at the most southwesterly point of Britain on Friday before it embarks on an 8,000-mile, 8,000-person journey around the country.

London organisers deliberately chose a lower profile relay than the ambitious international route for the 2008 Beijing Olympics after violent demonstrations against China's human rights record and its Tibet policy.

Some protesters hurled themselves into the path of the relay in London and campaigners tried to grab the torch or put out the flame.

Assistant Commissioner Chris Allison, national Olympic security coordinator, said he did not think Britain would see such disturbances.

"I sincerely hope we are not going to see those things ... I don't think we are going to get protests like that, I sincerely hope we don't," he told Reuters on Thursday.

"I hope the focus of the whole country will be allowing these 8,000 people who deserve the opportunity to carry the torch to be allowed do it."

The relay begins on Saturday, with Britain's most successful Olympic sailor, three-times gold medallist Ben Ainslie starting the 70-day journey.

Environmental demonstrations against some Olympic sponsors, including Dow Chemical, have already taken place, while a handful of locals were arrested after protesting against park land being used for Olympic facilities.

Britain has witnessed a number of violent protests in the past few years as the government implements austerity measures to combat a large budget deficit.

Allison said police were unaware of any specific requests to protest though various intelligence leads showed that people were "talking and thinking about it".

Detectives were watching the intelligence picture very carefully and he urged anyone planning to protest to notify the police.

A team of 28 trained police officers, who will wear a special uniform but be unarmed, will provide round-the-clock protection for the Olympic flame and its torchbearers, with some officers running between 15 and 25 miles a day.

The relay will go to the outer reaches of Scotland, Wales and Northern Ireland.

"Clearly we are looking at all the threats wherever the torch goes in the country and we're making sure we have an appropriate policing operation in place," Allison said.

Dissident nationalists opposed to Britain's control of Northern Ireland could pose a threat.

The threat from militant Islamists endures, seven years after suicide bombers killed 52 people in London.

Games officials were confident the torch relay would be respected.

"We live in a country where peaceful protest is very much a part of what we are, thank goodness in a way, so long as that doesn't slop over into becoming a public order issue or endangering people that are enjoying their day," London 2012 Chairman Seb Coe said in Athens ahead of the formal handover of the flame.

"I don't sense that there is a widespread feeling this (the relay) is something to be anything other than cherished actually.

"My gut instinct is that people will be quite protective of this...they won't welcome it being viewed as a vehicle for another malcontent."

The relay runners will include sports personalities, celebrities and locals nominated for their good deeds, most of whom will cover an average of 300 metres each.

The torch was lit from a flame kindled by the sun's rays in a ceremony at ancient Olympia. It will reach the British capital for the opening ceremony at the Olympic stadium in east London on July 27.

(Additional reporting by Georgina Cooper in London and Alan Baldwin in Athens, Editing by Tom Bartlett)

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