London mayor Boris Johnson admitted on Tuesday that there would be "imperfections and things going wrong" as the capital coped with the Olympics.
He said staging the Games was a "gynormous" task but the opening of the first Olympics-only road Games Lane and the first big arrival of competitors had gone well, despite negative stories emerging about driver confusion and athletes getting lost on the way from the airport.
Johnson said that the reported time of four hours for one competitors' bus reaching the Olympic Village in east London from Heathrow airport was "more like two-and-a-half hours".
He added that journey times from Heathrow could come down to around one hour and that, once in the Olympic Village, athletes reported being "bowled over" by facilities.
Johnson reiterated that "things are going very, very well" despite imperfections
Speaking in front of screens showing pictures of the state of London's roads, Mr Johnson said: "At the moment things are going very, very well. There will be imperfections, there will be things going wrong.
"But this is a gynormous operation."
Johnson was appearing alongside transport secretary Justine Greening at Southwark's Transport for London surface transport operations control centre, meeting the team monitoring the capital's traffic conditions.
Greening backed the Mayor up, saying: "The Olympics will be a challenge for London and challenge for transport in London."
Transport Secretary Justine Greening supported Johnson, calling the Games a "challenge" for TfL
Asked about possible drivers' confusion over the Games Lanes, she said: "There are a lot of signs up. Motorists are being given all the information they need.
"The Olympic Route Network (ORN) is obviously going to be disruptive for local residents but I hope they realise what an amazing experience the Olympics is going to be."
Heathrow Airport had "one of its busiest days ever" on Monday, but the longest queue was just 25 minutes, Prime Minister David Cameron's official spokesperson said.
"On London's roads, the reports of yesterday are that traffic was flowing well," the spokesperson said.
"The overall picture on transport is a good one. This is going to be a very, very challenging period for the capital, it's going to be more difficult to get around in the coming days and weeks, but the measures we are taking are working properly."