Walker Greenbank, a luxury interior furnishings group, reported a strong trading performance in the UK and accelerated international sales growth during the first four and a half months of the year.Total brand sales were up 8.9% year-on-year and 9.6% in constant currency driven by a good performance in its manufacturing and digital printing operations.UK sales rose 8.1% while in the US, thanks to the completion of its New York showroom, sales jumped 27.1% or 16.1% in constant currency.Ahead of its annual general meeting on Wednesday, chairman Terry Stannard said the board remains confident with the outlook for the remainder of the year and beyond.Investec analysts said the group's global growth opportunity is undervalued, with branded sales running ahead of the broker's forecast.N+1 Singer brokers noted: "With the stock having idled for the last 12 months there is a growing argument for the stock to perform again, particularly after witnessing the re-rating in adjacent consumer stocks."Shares rose 5.5% to 211p on Wednesday at 10:34.