Media playback is unsupported on your device Media caption Mr Sarkozy said: "Whether it be [German] Chancellor Merkel or myself, never will we turn our backs on the euro."

French President Nicolas Sarkozy has said France and Germany will never let the euro fail.

He acknowledged concerns about the future of the euro following bail-outs of Greece and the Irish Republic, as he addressed the World Economic Forum.

"Whether it be [German] Chancellor Merkel or myself, never will we turn our backs on the euro. Never will we abandon the euro," he said.

He added that those who bet against the euro should watch out for their money.

"The euro spells Europe. The euro is Europe and Europe has spelled 60 years of peace on our continent, therefore we will never let the euro go or be destroyed," he insisted.

France currently holds the presidency of the G20 and Mr Sarkozy was speaking about his vision for the group.

Dollar 'number one'

He is keen to negotiate a deal on currency reform during his tenure. But his call for a new international monetary system has received a cool response from the US, which sees it as an attempt to undermine the dollar.

The French president said he was not trying to weaken the US currency, adding that France was "deeply attached" to its friendship with the US.

"The dollar will continue to be the world's number one currency," he said.

He also called for the mandate of the International Monetary Fund (IMF) to be expanded to measure and enforce new rules on global economic imbalances.

He said the G20 should develop a set of indicators to define and measure imbalances on issues including currencies, trade and current accounts.

"I think it's worthwhile rethinking the IMF statutes to make it the organisation in charge of economic, financial and monetary policy co-ordination, and of enforcing the indicators."

French Finance Minister Christine Lagarde echoed these comments in a BBC World TV debate on global leadership.

"We want on the agenda of G20 the topic of global governance," she said, saying the roles of bodies like the World Trade Organization, the International Labour Organization and the UN's Food and Agriculture Organization - as well as the IMF - need to be looked at.

"We need to rebalance within those organisations and between the organisations so we can be effective and decisive not just in our speeches but in our actions," she said.