Tesco's UK sales have fallen over the past three months, in what the retailer said was "a challenging quarter for the industry as a whole".
Its like-for-like UK sales, excluding both petrol and VAT, declined by 1.5% in the 13 weeks to 26 May.
Tesco described the performance as "steady" and said it was outperforming the wider supermarket sector.
Its total global sales increased by 2.2%, "despite subdued consumer confidence in all our markets".
Back in April, Tesco announced that it was to spend £1bn on revamping its UK operation.
Tesco chief executive Philip Clarke said the company was now "rapidly implementing" this plan, with 4,300 extra staff having so far been recruited across 700 stores.
The company added that 100 outlets had now been "refreshed" since the start of 2012 and more than 145,000 employees had been given additional training.
Turning his attention to Tesco's overseas operations, Mr Clarke said: "Internationally, like-for-like sales growth proved resilient, despite slowing economic growth in China.
"Against the backdrop of continued uncertainty in the eurozone, it is pleasing to see that our businesses have largely sustained their performance."
Despite the fall in sales, Tesco said its profit target for the year ahead remained unchanged.
Clive Black, retail analyst at Shore Capital said: "We see this as a steady statement suggesting stabilisation is coming through in the UK."
Tesco added that since these latest figures, Diamond Jubilee celebrations had given it weekly sales of £1bn, its highest on record apart from Christmas.