The head of the Financial Conduct Authority, Martin Wheatley, said the regulator wanted to "take out" unscrupulous payday lenders.
He told Radio 4's Today programme.
Our concern has been that parts of this industry, not all, loan without doing any affordability checks and then loading costs onto people who simply cannot pay, and that's the part of the industry that we really want to take out, we want them to improve their standards or leave the industry.
More top news
Yorkshire Water says the tap water in Thorne, near Doncaster, is still not fit to drink after a contamination scare.
In December 2012, gunman Adam Lanza shot dead 20 children and six teachers in the Connecticut school, before turning the gun on himself.
The study, conducted by the European Banking Authority, looked at how much capital would be used up in adverse economic conditions.