ExxonMobil says it has had to use an elevated flare to manage a 'process upset' at its Mossmorran site.
But the firm insists the use of the flare is 'completely safe' and measures are being taken to cut its size and the length of time of flaring.
It has happened less than a fortnight since normal production resumed at the Fife Ethylene Plant.
The company released a short statement on Twitter earlier this afternoon.
It added its team is working to resolve the issue.
The statement read: "We are currently using our elevated flare to manage a process upset.
"Our team are working to resolve the issue.
"The use of the flare is completely safe and we will do everything we can to reduce size and duration."
In a further update, ExxonMobil says it has had to deal with a trip on one of its major compressors.
It added its team is conducting necessary checks needed before a safe re-start is carried out.
The company has apologised for any inconvenience to local communities.