Applegreen has closed one of its petrol stations after an online video showed a rat in a food preparation area.
In a statement to RTÉ News, Applegreen said it was carrying out an investigation following a "pest control issue" at one of its stations.
It came after a video widely circulated on the WhatsApp messaging service showed a rodent in the kitchen area of its Cherry Orchard site.
Ireland's ultimate breakfast roll. Only €4. pic.twitter.com/o5Fl2tnaSU— Tony Groves (@Trickstersworld) September 18, 2019
In the video, the rat is seen emerging from a rustling bread packet, before it moves across a shelf and climbs behind a silver oven.
The company said it was taking the incident very seriously, which it said "falls well below our high operating standards" and it is conducting a full investigation.
Fencing has been erected around the station and shelves and fridges have been removed to allow for a deep clean. Nearby drains are also being examined.
In a statement, Brennans Bread said its products are "made to the highest quality standards".
It said: "Our bread leaves our bakery in excellent condition. This incident is solely an issue for the service station in Cherry Orchard."
The Food Safety Authority of Ireland has said it was aware of the footage circulating on social media and it referred the matter to the HSE.
The HSE Environmental Health Service confirmed it had received complaints in relation to the video.
It said: "We take all complaints very seriously. An inspection has taken place and the matter is being fully investigated."
Additional reporting Fergal O'Brien