Olympics organisers are cutting parts of the opening ceremony to ensure it finishes in time for spectators to get home using public transport.
A stunt bike sequence has been slashed from the ceremony to try to avoid leaving spectators stranded.
The organising committee Locog has denied that the decision is connected to the G4S security debacle.
"Performers are rehearsing sections and transitions to ensure they are as tight as possible. This is normal in any production, whether it be theatre or ceremonies," said a Locog spokesman.
"We need to make sure the show comes in on time to make sure spectators can get home on public transport, so we have taken the tough decision to cut a small stunt bike sequence of the show.
We need to make sure the show comes in on time to make sure spectators can get home on public transport. - Locog spokesman
"We will be paying contracts in full and giving full credit in the programme. The show is set to finish between 12am and 12.30am."
A spokesman for TFL told Channel 4 News that it's "not a public transport problem" and the planned time for the ceremony to finish has not changed.
"The finish time isn't being brought forward, that's fixed and agreed. The concern is that the programme would overrun and go on after 1230," the TFL spokesman said.
The tube network will run until 230am on the night of the ceremony, with extra staff and services put on to cope with the crowds.
More than half of Londoners are not planning to change their travel plans during the games, according to research by car website Motors.co.uk, despite London transport's campaign urging commuters to plan in advance and 'Get ahead of the Games'.
Artistic director Danny Boyle said the £27 million spectacular, which will start at 9pm on July 27, will portray a traditional view of the British countryside.
Part of the stadium will be transformed into meadows for the performance, with horses, cows and sheep all featuring in the show.
The official opening of the Games will be seen by one billion people around the world, including the 62,000 ticketholders who will see the performance live at the Olympic stadium in Stratford.
Tickets to see the event cost up to £2,012 and organisers said on Tuesday that some of the more expensive seats were still on sale.
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