Coe also played down complaints about a miles-long traffic jam caused by the opening of the Olympic lane on the M4 highway from the airport into the city.
"I understand there was an accident at Reading, which slowed some stuff down, but the vast majority of people got through and it seems to be working quite well," he said.
The Olympic "Games Lanes" remain a contentious issue. Hundreds of London cab drivers blockaded the square outside Parliament on Tuesday, blaring horns and snarling traffic to protest their exclusion from the lanes. The cabbies claim it will be all but impossible to ferry passengers around once most of the special lanes take effect July 25.
Britain's notorious rainy weather may prove an even more intractable problem.
Coe said "we've got mops and buckets" to deal with the incessant rain that has soaked London for most of the summer. There is waterlogged ground at two key venues — rowing at Eton Dorney west of London and equestrian at Greenwich Park, south of the Thames River.
"It is a problem," Coe said. "It is causing us extra challenges now."
Organizers are resurfacing areas at the two venues, laying down temporary tracking for vehicles and spectators, and putting up special tent shelters to keep the workforce dry, he said.
Although forecasters say the weather could clear in time for the July 27 start of the games, Coe noted that organizers have contingency plans. Extra competition days were built into the schedule "as a last resort" for rowing and equestrian. There is an alternate course available for sailing events at Weymouth, in southeast England, and Wimbledon has a retractable roof over Centre Court for tennis.
Olympic Park, however, still resembles a construction site, with workers laying cables, installing seats and landscaping grounds Tuesday.
Not to worry, Coe said.
"Our venues will be open on time," he promised. "There is still stuff to be done, but it's about dressing up. We'll be ready."
Organizers also said they are reducing capacity at several stadiums hosting soccer matches after failing to sell all the tickets.
More than 1 million soccer tickets had been left unsold recently, but organizers cut the number by reducing capacity by 500,000 at the various venues, which means they might not open a section or a top tier of the stadiums.
Organizers said 250,000 soccer tickets are still on sale and that an additional 200,000 tickets will go on sale soon after being returned by national Olympic committees. A further 150,000 free tickets could be released for schoolchildren.
Associated Press writers Rob Harris, Paisley Dodds, Cassandra Vinograd and Jill Lawless in London, Eileen Sullivan in Washington and Tom Hays in New York contributed to this report.
Danica Kirka can be reached at http://twitter.com/DanicaKirka
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