Speaking before an EU summit in Brussels, Prime Minister David Cameron said:
"The eurozone needs a banking union, but Britain won't be part of it this union, and we've properly protected our interests in the single market."
"The countries in the Euro need to integrate more, need to integrate their institutions more," he added.
"But this change taking place does give us the opportunity to argue for the things that we want to do and get a better deal for Britain," he said.
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White House budget officials outlined the information during a telephone call with reporters given on condition of anonymity.