British Prime Minister David Cameron has threatened to veto a possible new European Union treaty designed to save the euro from collapse due to the European debt crisis.
Cameron said London would not support any treaty that did not safeguard what he describes as British interests.
Cameron said Britain's huge financial sector and the EU single market would have to be protected if his government was to support any new EU-wide treaty aimed at resolving fears over the possible collapse of the euro.
"The most important British interest right now is to sort out the problem in the eurozone that is having the chilling effect on our economy that I have spoken about," Cameron said.
"Now, that obviously means eurozone countries doing more together, and if they choose to use the European Treaty to do that, then obviously there will be British safeguards and British interests that I will want to insist on, and I won't sign a treaty that doesn't have those safeguards in it -- around things like, of course, the importance of the single market and financial services."
Britain does not use the euro, but France and Germany, which do use it, have been debating a potential treaty to strengthen integration and financial discipline among the countries that use the currency.
Reports say discussions have been focusing on a possible agreement between the 17 states that use the euro, as opposed to a pact that would involve all 27 EU states.
All EU members must agree on any bloc-wide treaty. Agreeing on a plan to resolve the euro crisis will be the focus of an EU leaders' summit opening on December 9.
Ratings agency Standard and Poor's has added pressure to the summit by announcing it has put the sovereign debt of almost all eurozone countries on review for a possible downgrade.
Reports say the warning means that Germany and France could lose their highest-level credit ratings without urgent action to resolve the debt crisis.
compiled from agency reports