Angela Merkel glances at British Prime Minister David Cameron during a State Banquet at the Schloss Bellevue Palace on the second day of a four day State Visit on June 24, 2015 in Berlin, Germany. Getty Britain's Prime Minister David Cameron will tell European Union leaders later today that Brussels must give the UK a better membership deal within the 28-nation bloc or face a withdrawal.

Britain's ruling Conservative Party is delivering a referendum by 2017 over whether Britain will stay part of the EU or not. The Tories are largely against leaving the EU and UK Chancellor George Osborne has explicitly said that he would prefer to stay within the EU and negotiate "a better deal."

Cameron will address prime ministers, chancellors, and presidents from the EU at 8 p.m. today and will implicitly say that Britain, the third biggest country in the bloc, may quit if it doesn't successfully renegotiate the terms of its membership.

The Guardian newspaper reports that there are four main points Cameron will address. The newspaper doesn't say what the points actually are but it does say that a "continental politician who has spoken to the prime minister" believes the UK PM may be listing themes rather than specific demands at tonight's meeting.

“David Cameron’s strategic approach is not to come up with specific things,” said the source.

It is perhaps unsurprising that Cameron would have to go in soft to tonight's meeting, considering some of the ire from EU politicians over the referendum.

“I didn’t ask for a referendum, but we have to deal with it,” said a senior figure in Brussels to the Guardian. “That’s why we have to contribute. It might be complete nonsense but I’m a politician. This is not really about content. It’s about politics and symbols.”

Pressure is mounting on Cameron after being allegedly snubbed by Brussels leaders last month when he tried to start negotiating the terms of membership within the EU.

He is also under pressure from prominent members of the business community in Britain, especially after they published a 1,000 page study, entitled "Change, or Go," stating that Cameron has to secure some "major reforms" to “introduce mechanisms to reduce the burden of regulation on businesses" or face a Brexit.

Over the last month, Prime Minister David Cameron was reportedly already putting plans in motion to bring forward an in/out referendum by a year. However last week, Cameron's office performed a U-turn and ruled out holding a European Union membership referendum on May 5, 2016.