Topaz Energy Group, Ireland’s largest convenience and fuel retailer, is being taken over by the Canadian convenience and fuel retailing giant Alimentation Couche-Tard, in a deal believed to worth about €450m (£324m).

The two companies have signed an agreement that will lead to the acquisition by the Canadian company of Topaz Energy Group together with linked companies Resource Property Investment Fund and the recently-acquired Esso Ireland. The transaction is expected to close in spring 2016, subject to the regulatory approvals and closing conditions.

Couche-Tard is one of the world’s biggest convenience and fuel retail businesses, with about 15,000 sites in North America (US and Canada), Europe (Norway, Sweden, Denmark, Poland, the Baltics and Russia), Asia and the Middle East. Approximately 100,000 people are employed in its network across the world.

The Topaz network comprises 464 service stations in the island of Ireland, 162 of which are company owned, and a commercial fuels operation with more than 30 depots. The business employs over 2,000 people.

Topaz chairman John Callaghan said: “The last two years have been a period of phenomenal development and improvement for the company. With the steadfast support of the board, our management and staff, we have established a well-capitalised group of growing businesses which, with the recent amalgamation of Esso in Ireland, is the undoubted industry leader.

“We are delighted to have agreed this transaction with Couche-Tard, which is recognised as a world leader in the fuel and convenience store industry. We know it will build on the foundations we have put in place and bring a new dimension to the industry in Ireland to the benefit of the economy, our customers and our staff. We wish Couche-Tard well and look forward with confidence to an exciting future.”

Emmet O’Neill, chief executive of Topaz, described the transaction as a “game changer’ for the retail sector in Ireland. He said: “Couche-Tard is one of the strongest names in retail in the world and their presence in Ireland will transform the retail sector here. I am thrilled that they have chosen Topaz as the foundation for their entry to the Irish market. They will bring enormous skill, energy and resources to this business and this market.”

O’Neill said that the deal followed a transformation of the company over the past two years, explaining: “In the last two years Topaz has moved from being a challenged business to one which has been transformed at every level and which now leads the market here. We have refinanced the company, upgraded the infrastructure, acquired and built new sites and convenience stores and ultimately acquired the business of Esso in Ireland. Today’s transaction is a reflection of the immense effort made by everyone on the team and across the company over that time.”