BUDAPEST--Croatian refiner INA d.d. (INA.ZG), a subsidiary of Hungarian oil and gas company MOL Nyrt.'s (MOL.BU), is losing $60 million a month by having halted production there, MOL's chief executive and chairman said Monday.

"We've invested $1 billion in Croatia so far, which is a lot. We're ready to relaunch production once the turmoil calms [in Syria]," Zsolt Hernadi said in an interview on commercial radio Inforadio.

INA suspended production in Syria in February as the internal political turmoil there compelled several foreign companies to withdraw.

Write to Veronika Gulyas at veronika.gulyas@dowjones.com

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