Retailer Tesco is exploring the sale of its South Korean operations, valued at about $6 billion, and has hired HSBC as a financial adviser, people familiar with the matter told Reuters today. 

The appointment of an adviser is Tesco's first concrete step towards a sale of a chunk of its Asian assets, although speculation has been rife about such a course of action. 

A sale would mark Tesco CEO Dave Lewis's biggest restructuring move since assuming charge last year. 

The retailer had received several inquiries in the past for its South Korean operations, its biggest business outside of the UK, which has encouraged the company to explore a formal sale process, the people added. 

Tesco and HSBC declined to comment. The sources declined to be identified as the discussions are confidential.

Tesco's other big Asian operation in Thailand had also previously attracted interest from Thai billionaire Dhanin Chearavanont who was rebuffed. 

The potential sale of the South Korean operations comes after Tesco unveiled in April its worst ever annual loss, hit by a one-off £7 billion write-down. 

The 96-year-old group, which has dominated the British retail landscape for decades, is going through a restructuring after hiring former Unilever executive Lewis. 

Tesco was distracted by expensive overseas expansion and failed to spot the threat from discounters at home, resulting in lost market share and declining profits. It was also hit by an accounting scandal and ratings downgrades. 

Global buyout firms KKR & Co, Carlyle Group, CVC Partners and TPG Capital Management as well as homegrown Asian buyout firms including MBK Partners are likely bidders for Tesco's South Korean business, the sources added. 

Tesco's South Korean operations generated £5.38 billion of revenue, excluding value-added tax for fiscal 2014/15, a 4% drop in like-for-like sales from the previous year, according to its annual report.

The South Korean operations generated about $750m in earnings before interest, tax, depreciation and amortisation (EBITDA) for the period and the business could be sold for seven to eight times EBITDA, one of the sources said. 

Tesco had 425 outlets in South Korea at the end of its fiscal 2014/15 year.