Selfridges, the owner of the Brown Thomas and Arnotts department stores in Ireland, has been put up for sale.

Selfridges' billionaire owners, the Weston family, have launched a formal auction to sell the historic department store business.

It is understood that advisers at Credit Suisse will start looking for a buyer, with the company valued at as much as £4 billion.

They will send out information memoranda - documents used to pitch the target to potential bidders - to begin the process, which could be completed by the end of the year.

It was first reported last month that the retail business could be sold after an unnamed bidder approached the Westons, who own a majority stake in Penneys owner Associated British Foods, with a move to buy Selfridges.

It is understood that no formal bid has yet been tabled but a small number of parties have already expressed their potential interest.

As well as the Irish stores, the business runs 25 stores worldwide, including its flagship Oxford Street store and Birmingham site within the Bullring.

The firm was founded in 1908 but has been controlled by the Weston family since 2003.

Selfridges has performed strongly in recent years, despite a wider downturn in the department store sector which has seen the collapse of Debenhams and declines at major rivals.

Meanwhile, Selfridges has seen a surge in profitability over the past decade as it has been boosted by heavy investment in stores.

But the group was still hit by the enforced closure of sites during the Covid-19 pandemic.

A year ago, the company cut some 450 jobs, around 14% of its total headcount, following the "toughest year" in its history.

It will now face the significant challenge of weakened footfall and fewer tourists in key areas.