Oil prices have posted their biggest drop in almost three decades towards $30/bl on expectations that an Opec-induced supply surge will exacerbate a global surplus, as demand growth collapses beyond Asia with the spread of the coronavirus to most major economies. The unravelling of co-operation between Opec and Russia to restrain oil output also throws the US shale sector and other non-conventional oil basins into their deepest crisis since at least 2015, as plummeting crude prices jeopardise higher cost projects from Canada to Brazil.