David Cameron has warned Europe it risks being left behind if the eurozone crisis is not resolved quickly and effectively.
Cameron told world leaders at the Davos economic forum that Europe faced a "perilous moment" and needed to sort out the problems of the eurozone with "boldness and real political will".
He said: "Tinkering here and there and hoping we'll drift to a solution simply won't cut it any more.
"This is a time for boldness not caution - boldness in what we do nationally, and together as a continent."
Cameron attacked the EU for its bureaucracy which, he said, made things "harder and can put tremendous burdens on businesses that can destroy jobs". He voiced his support for German chancellor Angela Merkel's call for deregulation.
Cameron told Davos delegates: "Here's the checklist. All proposed EU measures tested for their impact on growth; a target to reduce the overall burden of EU regulation; a new proportionality test to prevent needless barriers to trade in services; and slash the number of regulated professions in Europe.
"We can't afford to wait any longer."
On the euro, Cameron lectured the audience on how a single currency has worked successfully in other areas. "Look at the USA, look at the UK. Clearly, a single currency can work."
But he added: "What is important is to have a central bank that can stand behind [a single currency]. And to have the deepest possible fiscal integration that can deal with any shocks that may occur. The problem for the eurozone is not that it doesn't have some of these, but it doesn't have any."
Cameron tackled concerns that he was not a supporter of Europe, following his controversial veto in December in Brussels. "Nothing could be further from the truth. We are not walking away. We want to see Europe succeed," he said.