European equities closed lower on Friday as investors looked ahead to Sunday, when a referendum that could affect Greece's future in the euro zone will take place.
The pan-European FTSEurofirst 300 closed provisionally 0.6 percent lower on the day and more than 13 percent down on the week.
All major bourses in Europe closed in the red, with the benchmark French CAC index ending unofficially down 0.7 percent, the U.K. FTSE ending down 0.6 percent and the German DAX slipping 0.5 percent.
Greek stocks were closed this week.
European markets
All eyes were on the Greek referendum this weekend, at which Greeks will vote on whether to accept a creditor-proposed bailout deal conditional on further austerity. Voting "no" could jeopardize Greece's future in the euro zone.
Read MoreGreek referendum: Buy or dump the euro?
Capital controls on Greek banks will remain in place until after the vote. European Central Bank policymakers plan to next discuss emergency liquidity assistance for Greek banks on Monday, a person familiar with the matter told Reuters Thursday.
Banks slip on FX probe
Shares of some major banks in the U.K., including Barclays, RBS and Standard Chartered, closed more than 1 percent lower after Brazilian authorities said on Thursday that they were investigating 15 financial institutions on suspicion of rigging the Brazilian real in foreign exchange trading.
Read MoreBrazil probes currency market activity of 15 global banks
Meanwhile, K+S shares closed more than 4 percent higher on hopes of an improved offer for the German agricultural company from Canada's Potash Corp.
U.S. stocks were closed on Friday for the Independence Day public holiday.
Chinese stocks fell as much as 7 percent on the news that authorities in Beijing were investigating suspected market manipulation.
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