The consumer watchdog has accused payday loan companies of "irresponsible lending", "pressure tactics" and other bad practices.
The OFT has given them them 12 weeks to prove they provide an important service, or else they could face closure.
However, there will be no cap on interest rates.
Consumer Editor Chris Choi reports:
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The MK912 spitfire was forced to make an emergency landing soon after taking off.
Showers ease in the north tonight, with it becoming very warm in the southeast tomorrow.
A mass inhalation of "hippy crack" was carried out in the shadow of Parliament on Saturday in protest at the Government's drug policy.