Prime Minister Gordon Brown this afternoon rebuffed German suggestions of more EU Treaty changes - insisting that Europe's governments had already ruled that out for at least the next few years.
With the dust still settling on bitter battles over the failed EU constitution and the beleaguered Lisbon Treaty, Mr Brown moved swiftly at a Brussels summit to put down a marker for no more institutional upheaval.
He intervened after German Chancellor Angela Merkel said a summit pledge to look at "all options" to improve economic "governance" in Europe must include consideration of legal measures involving treaty changes if necessary.
The plan is for an EU "task force" to spend months looking at what the EU must do to reinforce joint efforts against any repeat of recent economic crises in the member states.
Mr Brown was asked after the summit if he had reminded the German Chancellor that the Lisbon Treaty was supposed to be the end of Europe's Treaty ambitions for a decade.
He replied: "I did say exactly that to Chancellor Merkel. It was a decision of not just Britain but of the whole European Council (of member states) that they did not want to see institutional and constitutional changes for the next few years."
He went on: "The working group - task force - will look at some of the issues that set out in the summit conclusions. We (the UK) will be on that task force and will put our views, so there is no suggestion that we will be bypassed in any of this. We will be part of that task force."
Any treaty adjustments would require unanimous approval of the 27 EU leaders, and any attempt at such an exercise would be greeted with dismay after the political struggle to get the Lisbon Treaty approved.
But the terms of the Greek bail-out plan endorsed by the 16 single currency member states at the Brussels talks leaves the door open for such a possibility.
It sets up a "mechanism" for coming to the rescue of Greece via loans from eurozone countries with "substantial" support from the International Monetary Fund if Greece signals it can no longer support its huge deficit and debt levels by funding on commercial markets.
But it also provides for new efforts to head off repeats of eurozone economic fallout on such a scale again, saying:
"We commit to promote a strong co-ordination of economic policies in Europe. We consider that the European Council(of EU leaders) must improve the economic governance of the EU and we propose to increase its role in economic surveillance and the definition of the EU growth strategy".
It asks Council President Herman Van Rompuy to set up a "task force" from the member states and the European Central Bank, "to present, before the end of this year, the measures needed to reach this aim, exploring all options to reinforce the legal framework."
If the chosen option included hefty new penalties against heavily indebted eurozone countries, with eurozone expulsion in extreme cases, as Chancellor Merkel has suggested, that would need a treaty change.
Earlier Mr Brown had stepped in to ensure the wording of the document was changed from promoting "economic government" for the EU to "economic governance" - a less contentious phrase avoiding suggesting the setting up of new institutions of centralised EU power.
Before returning to London Mr Brown emphasised that the UK would not contribute directly to the Greek bail-out plan if it is activated, and said it would not lead to the ceding of any powers from Westminster to Brussels.
The Prime Minister said he was "encouraged that the eurozone is meeting its responsibility", adding: "I can reassure people in the UK that we are not contributing directly to this and that none of these arrangements will see any powers being ceded from Britain to the EU."Reuse content