Royal Bank of Scotland (RBS) has posted a pre-tax loss of £1.26 billion for the three months to 30 September.
This compares to a £2 billion profit 12 months ago.
RBS has also become the latest bank to side aside more money against PPI claims.
It has set aside a further £400 million, taking its total charges for PPI mis-selling to £1.7 billion.
