Spar Ireland plans to introduce a new budget range in more than 100 stores across the Republic next month in a bid to reverse declining sales.

After a decade of growth during the Irish Celtic Tiger boom, Spar Ireland's sales fell almost 8% last year as the economy crashed and hard-pressed shoppers switched to Aldi and Lidl in increasing numbers.

Now it is hoping to win them back with a new S-Budget line of some 50 products that it claimed would be 40% cheaper on average than leading brands.

"We need an offering that gives us credibility as a high street brand in the area of value, which is what customers now want," said Spar Ireland managing ­director Willie O'Byrne.

Half of the products would be sourced through the company's bilateral agreement with Spar Austria and the other half from Irish producers, said a spokesman.

Spar Ireland is owned by the BWG Group, whose chief executive, Leo Crawford, said buying patterns had "changed massively" across Europe, and particularly in Ireland, in recent years.

"People are looking for value, no matter where in the world they are. Most people now know the unit price of the basic grocery items, and are seeking ­savings in every area."

It is "a very difficult time" for the grocery trade, he added, predicting a sales decline of 5% to 6% across the sector this year. "The retailers who will survive are those who adjust and that is what we have been doing," he said. "Spar has had a sales decline but that does not mean we are ­going downhill."