The UK's largest grocer, Tesco, has reported a 10% rise in group sales during the 12 weeks to 20 May.

That rise came despite what the firm described as the existence of the toughest ever trading conditions.

It said that first quarter sales in the UK were up 7.1%, rising 3.7% on a like-for-like basis and driven by a 3.9% increase in the volume of goods sold.

UK sales grew 4.2% on a like-for-like basis last year and Tesco says it has been cutting costs to reduce the effects of having to cut prices.

"These results demonstrate both focused strategy and innovative management in some of the toughest ever trading conditions," Tesco chairman John Gardiner said in a statement.

Tesco said in April that it had increased its UK market share to 15.5% based on till roll figures collected by industry body IGD.

Tesco's international business sales continued to grow strongly and, ignoring currency changes, were up 51.5% during the quarter.