THE HAGUE: Dutch-Belgian food retailer Ahold Delhaize said Wednesday that cost-cutting helped boost earnings in the third quarter, as it continues to unlock synergies from its merger more than a year ago.

Ahold Delhaize, one of the world's leading supermarket groups, said in a statement that net profit jumped by 54 percent to 362 million euros ($420 million) in the period from July to September.

Sales grew by 7.4 percent to 15.1 billion euros.

"We reported a strong financial performance again this quarter as margins increased significantly, driven by synergies" and cost-savings, said chief executive, Dick Boer.

In Europe, "our Dutch business continued to show good momentum with solid comparable sales growth and strong margins," the group said.

In the United States, "(our) sales performance further improved. We gained market share across our brands in a competitive landscape," it continued.

Ahold Delhaize said that its online business was also helping to drive growth, as consumers switch from conventional shopping to ordering online -- including food -- for home delivery.

"Our online businesses both in the US and Europe... in total grew more than 20 percent this quarter," the statement said.

"We continue to invest in online warehouse capacity and are on track to realize almost three billion euros in online consumer sales this year and nearly five billion by 2020."

Ahold and Delhaize finalised their merger in July 2016.

Between them, the firms have 6,500 stores in Europe and the United States, including such chains as Giant and Food Lion, and employ 370,000 people.

Analysts say the merger created the fifth-largest grocery chain in the fiercely-contested US market and the fourth-largest in Europe.