Former British prime minister Tony Blair warned on Sunday that the collapse of the euro would be "catastrophic" and urged Europe to move fast to support the currency. Blair said European leaders faced "very difficult and painful" choices and a "long-term framework of credibility" was needed to see off the crisis.
Speaking following the resignation of Italian Prime Minister Silvio Berlusconi on Saturday, Blair said there had "never been a tougher time to be a leader than right now".
But he said the "whole weight" of European institutions - including the European Central Bank - must get behind the euro if it was to survive.
He told BBC TV that economies had to align and that "the myth that the Italian and German economies were the same - that 10-year myth has now evaporated".
Measures required to bring stability to the euro would be painful, he warned, but added: "If the single currency broke up, it would be catastrophic."
Blair, who was premier for a decade until 2007, was also asked if his former finance minister Gordon Brown had been right to push hard for Britain to stay out of the euro when Labour was in power.