Lloyds chemist chain owner, Celesio AG, said it was asking competition authorities to look again at the planned merger between Boots Group Plc and Alliance Unichem Plc.

Germany-based Celesio, Europe's biggest pharmaceuticals trader, owns around 1,500 pharmacies in Britain, mostly under the Lloyds brand.

Celesio said in a statement it would be "raising concerns" with the Competition Appeal Tribunal about the Office of Fair Trading's (OFT) decision to conditionally clear the anticipated acquisition by Boots - Britain's biggest health and beauty retailer - of the UK drugs retailer.

"The public relies on community pharmacy as a frontline health service. We believe that such a significant change to the market requires further consideration," Celesio said.

"We will shortly be submitting an appeal to the Tribunal in relation to this case." On February 7, Britain's consumer watchdog said Boots could go ahead with its takeover of Alliance Unichem if the enlarged firm agreed to sell up to 100 shops to address competition concerns.

OFT said in a statement it had found around 100 local areas where competition would either be eliminated or reduced by the deal.

"However, Boots has offered divestment undertakings for all of these areas and the OFT is satisfied these will address its concerns," the regulator said at the time, adding: "If the parties do not give such undertakings, then the transaction will be referred".

Boots shares were 0.3 per cent up at 739-1/2p by 0934 GMT, valuing the business at nearly £3.6 billion, with Alliance Unichem stock up a similar amount to 936p, giving it a stock market value of almost £3.4 billion.

Celesio shares rose 1.1 per cent to 77.50 each.