Jan 19 - British online fashion retailer ASOS forecast year profit in line with market expectations after sales growth accelerated in its third quarter.

ASOS, which targets internet-savvy 16 to 34 year old women looking to emulate the designer looks of celebrities like Kate Moss, Sienna Miller and Alexa Chung but at a fraction of the price, said on Wednesday its retail sales rose 59 percent to 100.0 million pounds ($160 million) in the three months to Dec. 31.

That compares with an increase of 50 percent in its first half.

The firm said UK retail sales increased 23 percent to 56.3 million pounds, while international sales jumped 156 percent to 43.7 million pounds, helped by the introduction of United States, French and German websites in October 2010 and a free global shipping offer in the run up to Christmas.

International sales now represent 44 percent of ASOS' sales mix, up from 37 percent in the first half.

ASOS said it remained confident about the outlook.

Shares in ASOS have more than trebled over the last year, fuelled by buoyant trading and speculation the firm could attract a bid from companies as diverse as 18.3 percent Danish shareholder Bestseller, U.S. internet giant Amazon and British retailers Marks & Spencer and Tesco.

The stock closed Tuesday at 1,550 pence, valuing the business at 1.14 billion pounds.

(Reporting by James Davey)