Eurozone countries must act swiftly to tackle their levels of debt, Prime Minister David Cameron has said. In an address to Canada's parliament, he urged European leaders to show the "political will" to secure a "fundamental and lasting solution". Amid big losses on world stock markets, he admitted recovery from recession would be difficult. Labour leader Ed Miliband said the PM had "woken up to the crisis" but had not come up with a plan to tackle it. Mr Cameron told the parliament in Ottawa: "Endlessly putting off what has to be done doesn't help, in fact it makes the problem worse, lengthening the shadow of uncertainty that looms over the world economy. "We're not quite staring down the barrel, but the pattern is clear. The recovery out of the recession for the advanced economies will be difficult." 'Lecturing' Mr Cameron added: "Whatever course they take Europe's banks need to be made strong enough so that they can help support the recovery, not put it at risk. "At the same time we can not put off the fundamental problem of the lack of competitiveness in many euro area countries." BBC deputy political editor James Landale said Mr Cameron wanted Eurozone countries to integrate their tax systems more closely and use their bailout mechanisms more effectively to get business investing. His language was "stark and to the point", our correspondent said. Mr Miliband said the PM was "quite good at lecturing other people on getting their problems sorted out", but was not taking action himself. "All the prime minister seems to be offering is, 'I've got austerity here, I'm now going to export it.' That's not a solution to the problems the world faces," he said. "What we need is a plan for growth here at home and across the world. That's the way we tackle the debt issues that we face. The problem is the prime minister may have woken up to the crisis, but he doesn't have a plan to deal with it." Mr Miliband said there must be "co-ordinated action" from the leaders of the G20 industrialised nations. He called on Mr Cameron to persuade French President Nicolas Sarkozy - current head of the G20 - to call an emergency meeting of the group to "get a grip on the crisis". The G20 is due to meet in Cannes in November. In a separate speech in New York earlier on Thursday, Mr Cameron urged unity amongst members of the United Nations. He told the UN general assembly the international community must seize the "massive opportunity" of the spread of democracy in the Arab Spring.