BERLIN (Reuters) - Pilots at Lufthansa (>> Deutsche Lufthansa AG) will strike again on long-haul flights on Saturday, their union said on Thursday.

Pilots' union Vereinigung Cockpit (VC) grounded more than half of Lufthansa's long-haul flights on Thursday and is extending the strike to short- and medium-haul flights on Friday.

The union, which is trying to pressure management in a protracted row over early retirement benefits and cost cuts, said pilots would strike on long-haul and cargo flights on Saturday.

Lufthansa is trying to cut costs to levels nearer those of its rivals as it is squeezed by budget carriers Ryanair (>> Ryanair Holdings plc) and easyJet (>> easyJet plc) on European routes and airlines such as Turkish (>> Turk Hava Yollari AO) and Emirates [EMIRA.UL] on long-haul flights.

(Reporting by Emma Thomasson; Editing by Robin Pomeroy)