Morrisons boss David Potts has spent £500,000 buying more stock in the company.

The supermarkets share price has slumped by almost one quarter since he joined in March as Mr Potts tries to turn it around in a tough trading environment.

Morrisons said Mr Potts purchased 314,881 shares at 158.79 pence each on Thursday, taking his holding to 822,881 shares, worth about £1.3 million.

Last week the Bradford, northern England, based firm reported a plunge in first-half profit of more than one third to its lowest level in nine years.

Mr Potts has already warned "it will be a long journey" to move the company back into growth.

Last week Morrisons' chief financial officer Trevor Strain spent just under £100,000 pounds on 58,453 shares, taking his holding to 97,794 shares.