(Reuters) - British plus-size fashion retailer N Brown Group Plc (>> N Brown Group plc) reported a 10 percent rise in first-quarter product revenue and said it would shutter up to five loss-making stores, sending its shares to their highest in more than a year.

N Brown, whose brands target women aged 30 and above and those of a larger frame, said demand was strong for its women's clothing and reported a 16 percent rise in online sales in the 13 weeks to June 3, amid a tough trading conditions that have hit retailers.

Ladieswear and its Simply Be brand had a very strong period, with good responses to N Brown spring and summer campaigns, particularly JD Williams' "Spring into Summer" and Simply Be's "We Are Curves", the retailer said.

Rival Bonmarche Holdings Plc (>> Bonmarche Holdings PLC), which makes women's clothing in sizes 10-28, reported an almost 40 percent drop in full-year profit, and said the apparel market was hurt by lower demand, Britain's move to leave the European Union and unseasonal weather patterns.

Rising inflation and muted wage growth following the Brexit vote in June last year has forced consumers to rein in their spending.

British retail sales posted their biggest quarterly fall in seven years in the first three months of 2017, hurt by rising prices following the Brexit vote, reinforcing views that household spending, the main driver of the UK economy, was slowing sharply.

"Although the outlook for consumer confidence remains uncertain, our offering is resonating with customers," Chief Executive Angela Spindler said.

Analysts at Jefferies nudged up their full-year 2018 pretax profit expectations for N Brown by 1 million pounds ($1.3 million) and pushed up 2019 estimates by 2 million pounds, accounting for the store closures. Analysts at Peel Hunt upgraded the stock to a "hold" from "reduce."

N Brown said on Tuesday that it would close up to five Simply Be and Jacamo dual-fascia stores as a result of ongoing weak footfall in some locations.

Together, these five stores contributed 5 million pounds to revenue, but accounted for the entire 2 million pounds operating loss of N Brown's store estate in full year 2017, it said.

The retailer expects the process to complete by the end of August and sees exceptional costs between 10 million pounds to 14 million pounds.

Shares in N Brown were up 11.5 percent at 316.52 pence at 0753 GMT.

($1 = 0.7889 pounds)

(Reporting by Noor Zainab Hussain in Bengaluru; Editing by Amrutha Gayathri)

By Noor Zainab Hussain

Stocks treated in this article : N Brown Group plc, Bonmarche Holdings PLC