A confidential Bank of England (BoE) email, which was inadvertently sent to the Guardian newspaper, has revealed a secret project at the institution assessing the economic risks posed to Britain if the country votes to leave the European Union.
The existence of the Bank's project emerged as the Prime Minister insisted he was "confident" of securing reforms in Brussels after meeting with European leaders at a summit in Latvia.
David Cameron has made it clear he will start talks to renegotiate the terms of Britain's EU membership "in earnest" in the margins of today's European summit.
"These talks will not be easy. They will not be quick. There will be different views and disagreements along the way," the Prime Minister warned.
"But by working together in the right spirit and sticking at it, I believe we can find solutions that will address the concerns of the British people and improve the EU as a whole," he said.
"After all we are not alone in wanting to make the EU work better for people across Europe. And that is what I'm determined to do."
The Bank of England has launched a secret project looking at the economic risk to Britain if the country votes to leave the European Union.
David Cameron's hopes of limiting migration may actually be welcomed by some Eastern European countries.