Prime Minister David Cameron has warned that failure to act swiftly over eurozone debt would "lengthen the shadows of uncertainty" looming over the global economy.

In a speech before the Canadian parliament, the British premier called on indebted nations to make tough decisions in order to repair their broken balance sheets.

Surplus economies had a role to play too by stimulating demand, and refocusing spending to help deficit countries increase their exports, Mr Cameron suggested.

In Ottawa following a two-day visit to New York, Mr Cameron pressed home the need for quick action to avert the Eurozone crisis deepening.

Speaking on a day when global markets tanked, Mr Cameron called on European nations to show they had the "political will" to "do what is necessary."

He continued: "One way or another, they have to find a fundamental and lasting solution to the heart of the problem - the high level of indebtedness in many euro countries."

Banks had to be made strong, and lack of competitiveness challenged, he told Canada's parliament.

"Endlessly putting off what has to be done doesn't help, in fact it makes the problem worse, lengthening the shadows of uncertainty that looms over the world economy," Mr Cameron said.

High oil and food prices, the Japanese earthquake and stagnating growth in Europe and the US had hampered economic recovery, the PM added.

"We are not quite staring down the barrel, but the pattern is clear, the recovery out of the recession for the advanced economies will be difficult," Mr Cameron said.

PA