Germany and France have forged a pact to integrate the eurozone without reopening the EUs treaties, in a blow to David Camerons referendum campaign. Sidestepping Britains demands to renegotiate the Lisbon treaty and Britains place in the EU, the German chancellor, Angela Merkel, and the French president, François Hollande, have sealed an agreement aimed at fashioning a tighter political union among the single-currency countries while operating within the confines of the existing treaty.