CALGARY -- Imperial Oil Ltd. (IMO.TO) is warning regulators and customers that aviation gasoline shipped from its Edmonton-area refinery could cause interference with aircraft fuel gauge sensors.

The company says in a release that a product quality problem was discovered earlier this week at its Strathcona refinery and all shipments of "avgas" were immediately halted.

However, it says there were potential quality problems with fuel shipped since Dec. 28, resulting in a request to distributors to immediately stop selling the product. It says it has warned Transport Canada about the situation.

Imperial said it is not aware of any safety issues as yet related to the fuel. It said its fuel warning does not extend to aircraft that use jet fuel, also known in the industry as "Jet A."

Spokesman Jon Harding said avgas is mainly used in smaller planes but couldn't provide detail on how much fuel may be affected or where it was distributed.

Downstream vice-president Jon Wetmore said an investigation into the cause of the issue is ongoing and more information will be released as the situation evolves.