George Osborne has said Moody's message is "explicit" to carry on with austerity.
He says "we can either abandon our efforts to deal with debts" or we can "redouble our efforts" and make a brighter future for our children.
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PM spokesman's comments come following reports that the EU is secretly drawing up plans for greater military cooperation across the EU.
The Labour politicians put their alleged differences aside to jointly highlight how remaining in the EU could help fight climate change.
Late sunshine here and there this evening - but more cloud for southern Scotland, northern England and Northern Ireland again.