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ZURICH, Nov 11 (Reuters) - The Swiss National Bank (SNB)

SNBN.S said on Monday has added Zuercher Kantonalbank (ZKB) to its list of banks that come under closer supervision due to their importance to the wider financial system.

ZKB joins UBS UBSN.VX and Credit Suisse CSGN.VX , which are already considered systemically important by Switzerland's central bank.

In most jurisdictions, banks whose stability is considered essential for the well-being of the financial system are required to meet tougher regulatory requirements, such as holding a bigger capital cushion to protect itself against potential market shocks.

The SNB declined to provide details on Monday on the implications for ZKB.

ZKB confirmed the move, but declined further comment ahead of a media briefing scheduled for 1300 GMT.

(Reporting by Silke Koltrowitz; Writing by Mark Potter; Editing by Greg Mahlich)

((silke.koltrowitz@thomsonreuters.com)(+41 58 306 7454)(Reuters Messaging: silke.koltrowitz.thomsonreuters.com@reuters.net))

Keywords: SNB ZKB/