[TOKYO] The European single currency dropped below US$1.10 in early Asian trade on Monday amid growing concern Greece was headed for financial collapse and a possible eurozone exit.
Prime Minister Alexis Tsipras stunned Europe on Friday night with a surprise call for a July 5 referendum on the latest cash-for-reforms package and advised voters against backing a deal that he said spelled further "humiliation".
The European Central Bank said earlier on Sunday it would not increase its financial support to Greek banks.
The euro fell to US$1.0969 shortly before 7am (2200 GMT Sunday), from US$1.1160 in New York on Friday.
Mr Tsipras announced Greek banks and the Athens stock market will be closed on Monday and capital controls will be imposed, pleading for calm after anxious citizens emptied ATMs in a dramatic escalation of the country's debt crisis.