Topaz is in talks to take over Esso’s business in the Irish Republic, according to local press reports.
Esso has 38 company owned sites, and supplies another 60, and the reports say the deal would be worth about €70m.
A spokesman for Topaz would not comment on the deal, but Exxon Mobil has been trying to sell its Irish operations for some time.
The story first broke on radio station Newstalk which said the talks were close to conclusion.
Topaz is already the biggest player in the Republic with about 25% of the market comprising 120 company owned stations and 170 dealer-owned garages, and Esso currently supplies another 10% of the market so the deal would require regulatory approval.