The battle for Sears Canada is hotting up with reports in the US suggesting that major shareholder Sears Holdings has bought 400,000 shares in the company.

The move renewed speculation that it may be plotting a bid for the Canadian arm of its business.

In 2006, minority shareholder William Ackman blocked a takeover attempt by Sears Holding chairman Edward Lampert. It has been speculated that Lampert is particularly attracted by the C$820m (£447.7m) of cash that Sears Canada has on its balance sheet.