British Royal Bank of Scotland (RBS) on Friday reported a half-year loss before tax of 794 million pounds (1,270 million U.S. dollars) due to massive provisions for Greek government bonds and compensation for mis-selling of payment protection insurance (PPI).

Total loss after tax was 1.4 billion pounds (2.24 billion U.S. dollars) for the first six months of this year, said RBS, which is the last of Britain's five biggest banks to report half-year results.

The 84-percent-government-owned bank posted an operating profit of 1,871 million pounds for the first half of this year, compared with 1,132 million pounds of a year earlier.

RBS said it has put aside 733 million pounds for probably not getting back in full the money it had lent to the Greek government as a result of the country's debt crisis.

The bank also allocated 850 million pounds as compensations for customers who were mis-sold the PPI.

The bank's half-year report also showed a 1.25-billion-pound provision for losses at its Ulster Bank operations in Irish Republic and Northern Ireland.

Shares of RBS on London stock market plunged even 20 percent shortly after the opening on Friday, and was forced to a temporary suspension of trading, the third British bank to have had trading halted in the past 24 hours following Lloyds Banking Group and Barclays.