A company spokesman declined to provide further details of the affected units, saying that it was not the company's practice to discuss operational details of its units.
The company said last week that the plant was undergoing maintenance, which had caused flaring at the plant.
ExxonMobil's petrochemical complex located on Jurong Island is integrated with its refinery there and produces a range of feedstock and products such as polymers and aromatics.
(Reporting by Jessica Jaganathan; Editing by Christian Schmollinger)
