Discount retailers Aldi and Lidl are continuing to close in on their competition, the latest supermarket share figures show.

The numbers from Kantar Worldpanel for the 12 weeks ending March 30th show strong sales growth for both Aldi and Lidl, with respective growth rates of 21.9% and 11.1%.

David Berry is the commercial director at Kantar Worldpanel "Aldi has maintained a growth rate of over 20% throughout 2014. This has boosted its market share from 6.4% last year to a record 7.9%" he said.

"Aldi has capitalised by capturing more spend from its shoppers. Each shopping trip has grown by an average €2 per trip with two additional items being added to baskets".

"Lidl has also performed strongly with double digit sales growth for the fourth successive month. It posted a market share of 7.5% - just below its record 7.7% seen last August" he added.

Meanwhile, market conditions remain tough for both Tesco and Dunnes Stores - which have experienced sales declines of 6.6% and 3.9% respectively.

Tesco has continued to attract high numbers of customers through its doors, with the number of shopping trips falling by just 1%.

Its main challenge - Kantar says - is that these trips are shrinking in size, with customers picking up one item less per shop.

Dunnes' share of the market dipped below 22% for the first time in six months, as 40,000 fewer shoppers have visited the retailer this year.

SuperValu performed slightly behind the market, with sales dipping by 1.6% - leading to a fall in market share of 0.1 percentage points to 25.2%.