(Reuters) – ​Chevron Phillips Chemical Company, a joint venture between Chevron Corp and Phillips 66, has offered to acquire Nova Chemicals Corp for more than $15 billion including debt, people familiar with the matter said on Thursday. 

Chevron Phillips Chemical, one of the world’s top petrochemical producers, would gain scale and expand its footprint through the acquisition of Nova Chemicals, whose expandable polystyrene and resins are used in a range of industries, from construction to packaging. 

Abu Dhabi’s sovereign wealth fund Mubadala Investment Co, the owner of Nova Chemicals, has been exploring a sale of the Canadian plastics maker since the start of the year, and there is no certainty that it will accept the offer from ​Chevron Phillips Chemical, the sources said. 

Another bidder for Nova Chemicals may yet emerge, some of the sources added. Mubadala could also decide to keep a stake in Nova Chemicals in a deal, one of the sources added.