As Greece negotiates a potential bailout, Swiss airline Edelweiss is taking extra precautions when flying to the crisis-hit nation. Pilots have been told to carry more than $11,000 to cover costs, as the nation is largely operating on a cash-only basis.

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The cash is used to pay for “kerosene, handling or landing fees,” Edelweiss pilot Martin Gautschi tweeted in response to a question from Blick am Abend newspaper.

“The people are very helpful, the service perfect — despite the difficult situation,” Gautschi wrote.

The pilot added that all transactions are being conducted in cash, “just like in the last days of Swissair.” The comment references Swissair's financial difficulties when it became bankrupt in 2001 and airports would only accept cash for payment of fuel and airport services. Edelweiss is owned by Swissair and Lufthansa.

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Although the nation is operating in cash, money isn't easy to come by in the debt-ridden nation. Residents are limited to withdrawing €60 (US$66) a day from ATMs, but the cash machines have been running out of money and banks continue to remain closed.

Receiving cash from family and friends abroad is nearly impossible, as wire services such as Western Union and Moneygram have stopped transferring money to Greece until further notice, Schweiz am Sonntag newspaper reported.

Meanwhile, Greece's future remains uncertain. The country has officially asked for a three-year loan facility from the European Stability Mechanism (ESM) and agreed to quick reforms. Athens has promised to present a new plan by July 9.

The requested three-year bailout is estimated to be over €51 billion ($56 billion), although an exact amount has not been confirmed.

On Sunday, Greek citizens voted against accepting a proposal from creditors that would have meant more austerity measures.

Greece has previously received two bailouts, totaling $266 billion in loans.