Britain will defend its interests as the eurozone rallies to fight rising debt tensions, Chancellor of the Exchequer George Osborne said Sunday. The survival of the euro was \"hugely in Britain\'s national interests,\" he wrote in The Sunday Telegraph but warned that the rescue package for debt-laden Greece was bound to lead to more \"fiscal integration\" between eurozone members. Osborne, describing himself as a \"eurosceptic\", said Britain would be \"constantly alert for opportunities to protect and advance our national interests\" as the process gets under way. \"We must make sure we are not in any way excluded from key decisions on issues like the single market and financial service regulation that should remain the exclusive preserve of all 27 EU member states,\" he wrote. Under legislation passed this month, any major changes to EU treaties could trigger a referendum in Britain -- at which point London could begin to press for concessions from EU partners. \"The most significant decision the euro leaders took was to expand the scope and powers of the eurozone\'s bail-out fund,\" Osborne wrote. \"It can now buy the debt of countries in distress and fund bank rescues. These are very early days and we will see if the fund can use its new powers in a decisive and credible way.\" French President Nicolas Sarkozy \"describes it as a form of monetary fund for the euro. It is also another step on the road to further fiscal integration.\"