Interest-only mortgages
Interest-only mortgage repayments only pay off the interest. Payments may vary each month depending on the interest rate.
The capital is to be paid off at the end of the mortgage period in a lump-sum. This lump sum payment is normally paid from savings, pensions or an insurance policy taken out at the same time as the mortgage, such as an ISA or endowment policy.
The Financial Conduct Authority (FCA) is worried that there are many people with interest-only mortgages that are coming to the end of the loan term without them having the means to pay the capital part of the loan off. See
here on the FCA guidance for more information.