British supermarket Sainsbury's launched a clothing website on Thursday, providing wider access to its Tu collection as it seeks to build on the success it has had from expanding beyond food products in its stores.

The company, which trails market leader Tesco and is battling with Wal-Mart Stores' Asda to be Britain's second largest grocer, said the launch followed a successful 12-month trial.

The sales and profits of Britain's major supermarkets have been damaged by a fierce price war as the success of discount chains Aldi and Lidl has prompted them to slash prices for certain basic products. 

Expansion into higher margin non-food areas is providing some relief.

Sainsbury's began selling clothing in 1994 and in its 2014-15 financial year Tu clothing sales grew to 800 million pounds.

The firm is currently the UK's seventh largest clothing retailer by volume and 10th largest by value, according to market researcher Kantar Worldpanel.

A selection of Tu clothing is available in over 400 of Sainsbury's over 1,200 UK stores.

However, customers previously only had access to the full Tu clothing range if they lived near one of the 160 stores carrying the full collection.

The new website means a much wider range of items is now available for home delivery and click and collect. Some 710 stores will offer click and collect, including 112 convenience stores.

"Customers have increasingly been looking to buy Tu online, and we have seen a really positive reaction to the new site from the selection of postcodes that have had access to it over the past few months," said Sainsbury's director of online, Robbie Feather.

In June Sainsbury's posted a sixth straight quarter of falling underlying sales but said it believed its strategy was working.