Tesco shareholders are being urged to oppose changes to share option schemes at the grocer’s annual general meeting today.

Investor advisory service Riskmetrics is calling on shareholders to vote against the changes, which would extend to three years the one-year period in which leaving or retiring executives can exercise options.

It would apply to directors leaving due to injury, illness, disability, redundancy, retirement or a sale of the business.

Riskmetrics said that the change was “not in line with best practice recommendations”.

The Association of British Insurers has not issued an alert of breach of corporate governance but has warned investors of a potential breach in guidelines.

Tesco said: “In Tesco, many of our managers own and hold Tesco shares over a long period. This is about fair treatment to loyal staff members who leave us on good terms because of ill health, redundancy or retirement, and are losing out because of the current volatility – typically about 60 staff a year.”