Money to pay for Olympic tickets is to start to be taken from accounts.

The date to begin withdrawals was pushed back from last week until the ballots to sort out who gets tickets for oversubscribed events were carried out, London 2012 said.

The 1.8 million people who applied for Olympic tickets now face an anxious wait over the next few weeks to see if they have got tickets, plus how much or when money leaves their bank balances or credit cards.

A London 2012 spokesman told buyers: "People should make sure they have sufficient funds available from this date."

Organisers will be processing the applications through to June 10, and notification will be sent out by June 24 2011.

It means that in some cases, money will be taken out of people's accounts before they know exactly which tickets they have been successful in buying.

It will be a leap of faith for many sports fans since no-one yet knows who will be competing as many of the qualification events have not been run or the teams selected.

There are 6.6 million tickets on sale and more than 50% of the 650 sessions are oversubscribed.

Bids had been made for 20 million tickets by the time the six-week application deadline closed on April 26.

The thrill of seeing a home-based Olympics, often dubbed by London 2012 as a once-in-a-lifetime event, has led to fears that some people have been seduced in to over-bidding.