ATHENS (AFP) – A Financial Times report that Greek savers could lose 30 percent of their bank deposits to shore up their country’s banking system is a “malicious rumour,” Greek Finance Minister Yanis Varoufakis said Friday.

“FT report of a Gk (Greek) Bank Bail In is a malicious rumour that the Head of the Greek Banks Association denied this morning,” he tweeted.

The British business daily, quoting unidentified quoting bankers and businessmen close to negotiations, had reported that Greek depositors with over 8,000 euros ($8,900) in an account may be made to take a “haircut” similar to those taken by Cypriot account holders in 2013, when uninsured funds were seized to stabilise the financial sector.

“It would take place in the context of an overall restructuring of the bank sector once Greece is back in a bailout programme,” said one of the sources.

Greek banks have been shut since Monday, and the system faces collapse if the European Central Bank (ECB) declares them insolvent should Greece refuse to pay back its debts.

Greek Prime Minister Alexis Tsipras has called a referendum for Sunday to asks Greeks whether they are willing to swallow tougher austerity measures in return for bail-out funds from its creditors, the International Monetary Fund, the European Commission and the ECB.