Greece crisis: PM Tsipras lashes out, and Lew urges a deal

U.S. markets followed their Asian counterparts sharply lower on Monday after Greece failed to strike a deal with its international lenders to secure more funding.

The debt-stricken country introduced capital controls and said it will keep its banks shut for much of the week—all leading up to a referendum on Sunday that some are casting as a decision on whether to stay in the euro zone.

S&P downgraded the country's long-term credit rating from CCC to CCC- with a negative outlook. The ratings agency said it saw a 50 percent probability that Greece would exit the euro zone.

Soon after the downgrade, Greek Prime Minister Alexis Tsipras sat for an interview with a local outlet. He blasted Athens' creditors, whom he accused of conspiring to "wipe out hope," and called for his country to vote "no" in the upcoming referendum.

Here's the latest Greece coverage from CNBC:
Greek crisis stokes bitcoin prices higher
7 things investors need to know about the Greek crisis
Greek referendum gamble by Tsipras unleashes chaos
Grexit is tragedy for Greece, but 'Apocalypse Not': Strategist
ECB forces Greek people to decide: Robert Hormats
Greece could face social unrest soon: Wilbur Ross
Capital controls: Greeks and tourists to be hit hard
Global markets slide on Greek crisis fears
Will a Greek tragedy be the euro's downfall?

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