Olympic organisers sought on Tuesday to reassure Londoners that the city's traffic would not grind to a halt because of measures designed to speed the journeys of athletes and officials going to Games.

The roads around London are relatively narrow and clogged at the best of times and some sceptics fear that transport could prove the biggest problem during the July 27-August 12 Games.

Transport problems at the 1996 Olympics in the U.S. city of Atlanta led to critical headlines around the world.

Special restrictions on stopping and turns will apply on a 109-mile Olympic Route Network (ORN) linking the main venues to accommodation -- a proposal that has irritated some Londoners who say they face delays while VIPs are whisked past at high speed.

Transport planners dismissed such fears as myths.

They stressed restrictions would typically only be put in place a couple of days before the Games, rather than stretching on all summer and emphasised the route remained open to all traffic and covered just one percent of the capital's roads.

A large proportion of London will be unaffected by the Games, Leon Daniels, managing director of surface transport at Transport for London, told a news conference.

Express lanes reserved for those involved in the Games will be put in place but these will cover only 30 miles. Planners will be able to open them up to all traffic if the roads are clear enough.

Anyone straying into a Games lane faces a penalty fine of 200 pounds.

(This version has been refiled to fix typo in headline)

(Reporting by Keith Weir; Editing by Sonia Oxley)