The discussions are at an initial stage and no agreement has been reached, the companies said Sunday. Saudi Industrial owns 50 per cent of National Petrochemical, and they had attempted a merger nine years ago. National Petrochemical’s shares closed at the highest level since 2014, giving it a market value of about 15 billion riyals ($4 billion). Saudi Industrial ended 5.5 per cent higher in Riyadh. The possible merger comes as energy companies in countries such as Saudi Arabia, Qatar and the United Arab Emirates restructure their operations to cope with a market that’s under strain from lower demand. National Petrochemical’s shares closed at the highest level since 2014, giving it a market value of about 15 billion riyals ($4 billion). Saudi Industrial ended 5.5 per cent higher in Riyadh.