By Carla Mozee, MarketWatch

U.K. stocks fell Friday, locking in a weekly loss as bank stocks came under pressure and as Greek-crisis uncertainty weighed on European assets.

The FTSE 100 fell 0.7% to 6,585.78, with all sectors ending lower. The benchmark fell 2.5% for the week, its worst weekly loss since mid-December, FactSet data showed.

In the banking group, Royal Bank of Scotland Group (RBS.LN) fell 1.9% following a Financial Times report (http://www.ft.com/cms/s/0/6a30cb4e-20d5-11e5-ab0f-6bb9974f25d0.html#axzz3eoGwNIAw) the lender is looking at $13 billion (GBP8.32 billion) legal bill from a U.S. Federal housing agency. The bill would resolve claims it misled buyers of mortgage-backed securities, and the legal bill RBS is facing is bigger than analysts had anticipated, the FT reported.

Meanwhile, Brazil's antitrust agency said Thursday it is investigating a number of banks (http://www.marketwatch.com/story/brazil-probes-banks-on-suspected-rate-manipulation-2015-07-02) on suspicion they created a cartel to manipulate the exchange rate of Brazil's currency, the real. Standard Chartered (STAN.LN) lost 2.1%, and HSBC Holdings PLC (HSBA.LN) (HSBA.LN) fell 0.9%.

BP PLC (BP.LN) shed 0.7%. That move sliced into a 4.4% gain Thursday after the oil major said it would pay $18.7 billion over 18 years (http://www.marketwatch.com/story/bp-to-pay-187-billion-to-settle-deepwater-claims-2015-07-02-94853311) to settle all U.S. federal and state claims arising from the Deepwater Horizon oil spill in April 2010.

Equipment rental company Ashtead Group PLC (AHT.LN) was among Friday's few gainers, picking up 1.4%.

U.K. and European stocks fell ahead of Sunday's referendum in Greece, asking voters whether to say yes or no to lenders' bailout terms for the debt-laden country. European equity indexes (http://www.marketwatch.com/story/european-stocks-wobble-ahead-of-greek-referendum-2015-07-03) logged looking at sizable losses for the week, as well. Read: Know this about Sunday's Greek referendum (http://www.marketwatch.com/story/know-this-about-sundays-greek-referendum-2015-07-03)

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