A shortage of drivers is being blamed for an increase in bus cancellations in Wellington

Last Wednesday, 70 services were cancelled at the last minute.

Metlink has now confirmed it's short of between 40 to 50 drivers.

General manager Scott Gallacher says drivers are facing fatigue after a year operating as essential workers in the pandemic.

He says many are over 60, making them a more vulnerable age group and they're taking sick days if they feel unwell - in line with the Government's Covid-19 messaging.

Metlink data shows cancellations increased from five-hundred in January to more than 12-hundred in March.