Visitor and sales assistants working at the National Maritime Museum, Queen’s House and Royal Observatory Greenwich were balloted after the imposed changes.

48 of the 73 people balloted responded, representing a 68% turnout which is well over the 50% level required to validate industrial action. One ballot paper received was spoilt.

Members were asked whether they were prepared to take part in strike action and if they are prepared to take part in industrial action short of strike.

37 members said they would be prepared to take part in a strike and 10 voted no, meanwhile 41 members supported action short of a strike and 1 member voted no.

During the ballot period, Royal Museums Greenwich notified staff they will receive an additional 1% of salary from December this year which is welcome news. Prospect is taking stock of the ballot result and members’ views and will be notifying Royal Museums Greenwich of next steps in due course.

Caroline Hemmington Prospect negotiations officer said: “Members have been left with no other option but to consider strike action after having changes imposed on them.

“These terms and conditions leave staff worse off than before and we will do everything we can to ensure that they get the fair deal they deserve.”