Britain's Deputy Prime Minister Nick Clegg said Sunday it would be "extraordinarily grave" if no agreement was reached on saving the eurozone at this week's EU summit. European Union leaders gather in Brussels on Thursday and Friday to thrash out a way to save the 17-country single currency bloc, likely with proposed treaty changes to create closer fiscal union and economic governance.
"It is extraordinarily grave if no agreement is reached," Clegg told BBC television.
"We need to have a clear roadmap towards a stabilisation and strengthening of the eurozone." He said the eurozone rules should be toughened up, and blamed Paris and Berlin for causing much of the present woes by breaking the existing rules themselves.
"Those rules were not adhered to. That's the great tragedy. And, bluntly, it was the French and German governments back in 2005 who signalled that there was going to be a free-for-all.
"If those rules had been stuck to in the first place, we wouldn't now be in the trouble that we now face.
"It's right that they should be strengthened."
Clegg said German Chancellor Angela Merkel is "right when she says that the design of the currency as it is lop-sided and needs to be changed".
Clegg also warned against turning the eurozone issue into a wider debate on the EU - something which many members of Prime Minister David Cameron's eurosceptic Conservatives, the main party in government, would like to do.
Clegg is the leader of the Liberal Democrats, the europhile junior members of Britain's governing coalition.
"I would like to see those rules strengthened with the minimal amount of institutional fuss because I think if you open this whole thing up into a naval-gazing exercise, then that would be very damaging to the urgent need to make sure that we fix things in the eurozone."