In his speech to business leaders, David Cameron is expected to acknowledge that we're living in "perilous economic times".
"Turn on the TV news and you see the return of a crisis that never really went away: Greece on the brink…the survival of the Euro in question," he is expected to add.
"Faced with this, I have a clear task: to keep Britain safe.
"Not to take the easy course - but the right course."
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