BELGRADE // The US secretary of state said on Thursday that ISIL can be defeated within “months” of a ceasefire between Syria’s government and moderate rebels. Speaking in Belgrade at a security event, John Kerry urged the world to come together behind a peace strategy recently hashed out by the United States, Russia and other countries.Meanwhile, the UK became more involved in the fight against ISIL yesterday, with British warplanes hitting oilfields in eastern Syria used to fund the extremist group. The strikes came hours after British lawmakers voted 397 to 223 to support prime minister David Cameron’s plan to extend air strikes from Iraq to Syria.