brussels ireland need election talk term britain exit european union enter crucial phase avoid physical border ireland northern ireland irish foreign minister simon coveney say friday irish government verge collapse thursday party whose vote prime minister leo varadkar depend pass legislation say would seek remove deputy prime minister breach cooperation agreement ireland need election right reason frances fitzgerald force resign issue discussion investigation tribunal agree set coveney say main opposition party ... risk election time really really serious issue government manage national interest say refer brexit negotiations ireland need election amid crucial brexit talk coveney