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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Remaining largely cloudy with patchy drizzle over hills. Becoming milder, breezy with some brighter breaks in the west on Friday
Saturday looks like the best day of the weekend. Mainly dry for both Saturday and Sunday but a cooler, cloudier finish
Another largely cloudy and murky day. Perhaps a little brighter and feeling milder for Friday