Woolwich ferry workers will strike again in February and March in an ongoing bid for better pay.

Unite members voted unanimously to down tools on the ferry for 24 hours on February 28 and March 13.

They claim not all staff are paid the London Living Wage, and object to changes to shift patterns that have normalised weekend working.

The free service carries more than 7,000 people and almost 3,000 cars across the river every day at Woolwich.

It is run by Scottish firm Briggs Marine Contractors, on behalf of Transport for London (TfL).

But Unite claims the lowest paid workers receive less than the London Living Wage – currently £10.75 an hour.

This is mandatory pay for all staff, as both Briggs and TfL are Living Wage accredited employers.

The contractor denies the union’s claim, saying all staff are paid above the minimum.

Their dispute hinges on how the Living Wage is calculated – total pay for ferry staff meets the threshold, but a significant proportion of their salaries come from add-ons for extra duties.

Only guaranteed bonuses can be included with basic pay when calculating the Living Wage, according to its accreditor, the Living Wage Foundation.

The fair pay organisation says anything dependent on job performance is not allowed.

But the Mayor of London, Sadiq Khan, says all ferry workers already receive the minimum.

Speaking at Mayor’s Question Time earlier this month, Mr Khan said he had “checked out” the dispute and believed all workers were being paid the London Living Wage.

He called on Briggs and the union to “roll their sleeves up, get round the table and resolve this issue”.

Today TfL Sponsored Service Manager Danny Price confirmed that Briggs is Living Wage compliant:

He said: “We require all contractors working on our services or sites to pay the London Living Wage as set out by the Living Wage Foundation, and take any suggestion that a contractor may not be complying seriously.”

But Unite regional officer Onay Kasab said Briggs have a “dismal record” on relations with their workforce.

He said the company “slice and dice the pay of an already low-paid workforce”.

Mr Kasab today called on Transport for London (TfL) to review its contract with Briggs.He added: “Unfortunately, it is the travelling public who will bear the brunt of the company’s unacceptable behaviour to its staff.”

A spokesperson for Briggs said: “We continue to press for meaningful negotiations with Unite, and call on the union to suspend the reported strikes to prevent further disruption to the travelling public.”

Briggs has run the ferry since 2012, and their contract will be reviewed later this year.

In November, the Mayor apologised for delays on the service caused by the introduction of new energy-efficient boats.

He said he was considering whether TfL should run the service when the current contract ends.