U.N. to hold Libya conference as planned despite surge in fighting: envoy

G7 foreign ministers warned eastern Libyan military commander Khalifa Haftar to halt his thrust on Tripoli, menacing the internationally recognized government based there, or face possible international action.Haftar's Libyan National Army (LNA) said on Friday its forces had advanced into the capital's southern outskirts and taken its former international airport.Its spokesman Ahmed Mismari said 14 LNA troops had been killed so farThe offensive by the LNA, which is allied to a parallel administr