Harry Ramsden's owner Ranjit Boparan has shown an interest in adding Northern Foods to his empire.

But an initial approach by letter, possibly the precursor to a £300 million offer by his Boparan Holdings group, was swiftly rebuffed by Northern Foods bosses.

Northern Foods, which owns Fox’s Biscuits, remain determined to press ahead with a proposed merger with Irish chilled foods firm Greencore, which is the UK’s biggest sandwich maker, and they have urged shareholders to vote for the deal.

The Northern Foods board confirmed it had received an approach from Boparan Holdings asking for information about the company.

Mr Boparan – one of Tesco’s biggest chicken suppliers and owner of the Harry Ramsden’s and FishWorks chains – is now going through Northern Food’s books after asking for access in a letter last week.

Northern Foods said Boparan Holdings had not made any offer or indicated the price at which it would make an offer.

Mr Boparan has been building up his stake in Northern Foods since the Greencore merger was announced, from less than three per cent to a 6.6 per cent shareholding.

The entrepreneur now has access to the same financial information offered to Greencore, as is allowed under City takeover rules. Last month, Northern Foods announced plans to merge with Greencore to create a business called Essenta Foods with sales of £1.7 billion.

Northern Foods said the board continued to back the merger with Greencore.

Harry Ramsden’s, which includes the world’s biggest fish and chip restaurant at White Cross, Guiseley, was acquired by Boparan Ventures, run by Midlands-based entrepreneur Ranjit Boparan, in January.