By Saabira Chaudhuri

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LONDON--Wm. Morrison Supermarkets PLC's new chief executive is slashing roughly one third of the jobs at its head office, continuing his overhaul of the U.K.'s fourth largest supermarket chain.

The Bradford, England-based retailer will cut 720 jobs at its head office, where the number of people employed has jumped 50% since 2008 to more than 2,300. At its supermarkets, the company is recruiting 5,000 staff to increase availability and open more check outs.

"We are focusing on the things that matter to our customers. That means having more of our staff in our stores, improving product availability and helping customers at our checkouts," said Morrisons Chief Executive David Potts. "To support this, we need a simpler, faster and cost-conscious head office and that requires some tough but necessary decisions."

Britain's supermarkets are in the midst of a fierce battle for market share with German discounters Lidl and Aldi, which attracted customers during the recession with their bargain prices. The latest data from industry body Kantar shows that Morrisons lost market share in the 12 weeks running to the end of March.

Morrisons' moves come as rival Tesco PLC--Britain's largest supermarket chain--has also been putting more staff on the shop floor as part of a larger move to defend market share. Tesco's new CEO Dave Lewis has closed unprofitable stores and reduced Tesco's product lineup, and has also said he wants to sell some noncore assets.

The company is also closing its sprawling headquarters in Cheshunt, relocating to its Welwyn Garden City office.

Mr. Potts, who took the helm at Morrisons last month, has already made some bold moves to turn the company around. Earlier this week, the retailer's trading director Casper Meijer left, after Mr. Potts said the company needed someone "who will dedicate all their efforts to living and working here in Britain." Mr. Meijer's family was in the Netherlands and he shuttled back and forth between the two countries.

Seven of the ten members of Morrisons' management board who were in-place when Mr. Potts arrived at the company last month have since left the business, notes Shore Capital analyst Clive Black. "He is materially imposing his authority on a company where trading performance simply has not been good enough for some time," said Mr. Black.

Last month, Morrison took a huge property write-down, reporting a large loss for the fiscal year, as it disclosed it would close stores and lower its dividend.

Write to Saabira Chaudhuri at saabira.chaudhuri@wsj.com

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