LONDON--London needs to find a new mountain biking course for the 2012 Olympics after its original venue was deemed too easy.

  London organizers said Friday that the International Cycling Federation, or UCI, wanted a more challenging course than the one at Weald Country Park in the county of Essex, 25 kilometers (15.5 miles) east of the Olympic Park in east London.

  The site had been approved by the UCI in London's bid file, but organizing committee spokeswoman Jackie Brock-Doyle said the course requirements were getting tougher as the sport was evolving.

  "The UCI has asked us to find a course that meets new and challenging requirements that test the best mountain bikers in the world in 2012," Brock-Doyle said.

  "Whilst this is disappointing news, we have agreed that, together with Essex County Council, we will look at other possible venues within Essex that meet the new requirements of the sport."

  Mountain biking was first contested at the 1996 Atlanta Olympics. The International Olympic Committee describes the event on its Web site as involving cyclists "riding over what is usually a very hilly, sometimes mountainous course, usually on natural terrain.

  "They may need to maneuver over trees, branches, rocks and streams," the IOC said.

  It's the second time that London 2012 officials could be forced to change a venue.

  In October, London officials said the venue for the canoe slalom events might have to be moved because of contamination at the original site in Spitalbrook to a site 9.6 kilometers (6 miles) away.

  A final decision could be reached this month.

  And last month, British Shooting officials wrote to all the British lawmakers saying they were unhappy with the venue for their events _ a temporary venue at the Royal Artillery Barracks in Greenwich, southeast London _ saying it would leave no legacy for the sport.