Two national museums are shut for a second day today after workers walked out in a dispute over pay.

Around 100 Public and Commercial Services (PCS) Union workers at the National Museum of Scotland went on strike at 1.30pm yesterday after a breakdown in talks.

The union said it is attempting to get museum management to reverse its decision to remove weekend working allowances for staff.

The National Museum of Scotland (NMS) and the National War Museum in Edinburgh were closed yesterday afternoon and remain closed today as a result of the strike.

They will be open as normal tomorrow.

Lynn Henderson, PCS Scottish secretary, said: ''It was only a few weeks ago that the National Museum Scotland topped the poll as the most visited tourist attraction in Scotland, but they have come bottom of the league this week for poor industrial relations.

''Museum management and Scottish ministers have proved to be intransigent throughout the process. It is interesting that Scottish ministers approve £7 million to pay a bonus to prison officers but turn a blind eye to the lowest paid workers being stripped of payments for weekend working.

"Our members are now forced to take strike action again and have indicated that their resolve remains strong.''

A spokeswoman for National Museums Scotland apologised for the inconvenience caused to visitors to the museums.

She said: ''Like many other public sector organisations, National Museums Scotland has had to make a wide range of changes in order to manage the reduced budgets which have been a result of the financial crisis.

"These changes have included reducing staff numbers, reducing a range of budgets, constraining some services and introducing a change to some terms and conditions for staff newly appointed to ensure that we could continue to operate within the funding available.

''National Museums Scotland supports public sector pay policy and delivers the Scottish Living Wage for all its employees. Over recent years, including the period when a public sector pay freeze was in place for the majority of staff, we have differentially increased pay levels for our lowest paid staff.

''Weekend payments are no longer common in the culture and tourism sector across the UK. In January 2011, National Museums Scotland introduced revised contracts for new staff who are employed to work weekends; these new contracts do not include weekend working allowances.

''We explicitly communicate the terms at key stages of recruitment and on appointment. No member of staff has received a pay cut following the introduction of new contracts. Existing terms and conditions have been preserved for all staff employed prior to 2011.''