Britain hinges on a Brexit as David Cameron is left out of EU treaty talks

It is a distinct possibility that Britain could leave the European Union, when the Conservative party presents the country with an in-out referendum by 2017, as Prime Minister David Cameron is already failing to negotiate "a better deal" for the UK within the 28 member bloc.

Over the last few days, Cameron was in Brussels to try and start negotiating the terms of its membership within the EU. However, according to France's Le Monde newspaper as reported by the Guardian, Germany and France sidestepped Cameron's demands to renegotiate the Lisbon Treaty and sealed a pact to "integrate the eurozone without reopening the EU's treaties."

Le Monde says that the French and German proposals will be presented at the EU summit in Brussels in June, while Cameron will unveil his list of changes Britain wants, if the country is to stay within the bloc.

The Lisbon Treaty is the successor to the European Union Constitution, which became law in 2009. It includes heightened powers for the European Commission, European Parliament and European Court of Justice. It also opened the doors for more freedom of movement between EU members and greater control from Brussels over the final say for asylum applications.

Though the Tories are pushing through the promise of a referendum, however, the party is largely against leaving the EU.

In January last year, UK Chancellor George Osborne said the Tories were determined to deliver on the promise of a referendum but they would prefer to stay within the EU and negotiate "a better deal."

"Our determination is clear: to deliver the reform and then let the people decide," Osborne said in a speech at a Tory party conference on January 14. "It is the status quo which condemns the people of Europe to an ongoing economic crisis and continuing decline. And so there is a simple choice for Europe: reform or decline."

Senior Brussels officials have repeatedly said they were not keen to reopen the Lisbon Treaty. However, Le Monde says the French and German proposal to strengthen the integration of EU member states without reopening the treaties will shut the door on Britain renegotiating its terms of its membership.

This could be a huge blow to Cameron's Conservative party to drum up support for Britain to stay within the EU.

Only four days after Britain's General Election this month, ING's senior economist James Knightley warned that the UK's status as an EU member is on a knife edge.

ING warned that the 3.8 million people who voted for the UK Independence Party, which is opposed to staying in the union, could be a massive threat to Britain's membership. The amount of people who voted for UKIP was larger than the Liberal Democrats and the Scottish National Party combined.

The latest Eurobarometer public opinion survey shows just 23% of Britons have a "generally positive" view of the EU, with only Greece having a lower rating (22%), highlighted ING. Furthermore, immigration topped the monthly Economist/Ipsos MORI poll when people were asked: "What do you see as the most important issue facing Britain today?"

Immigration/immigrants was the top answer at 37%, with the economy on 33%.