A union representing workers at the National Museum of Scotland has said its members will stage a series of weekend strikes.

The Public and Commercial Services (PCS) union said the move was a "major escalation" in the dispute over working allowances.

Industrial action will take place during Easter, March 26 and 27, followed by five more weekend strikes taking place throughout April and the beginning of May.

Previous strikes held on Boxing Day and at Easter have closed the flagship museum to the public.

The union said it chose to escalate the dispute after talks with management resulted in no new offer.

PCS said was also disappointed SNP ministers had not intervened when its MPs voted in support of weekend premium payment for Scottish shop workers.

Lynn Henderson, PCS Scottish secretary said: "Our members at the museum are angry that this dispute has dragged on so long.

"These low-paid workers are withdrawing their labour in frustration at their management’s intransigence and the two-faced hypocrisy of SNP leaders to support weekend premiums for shop workers whilst denying the same allowance to public sector workers employed by their own administration.”

A National Museums Scotland spokeswoman said it was "regrettable" the strike would affect Easter visitors but that at least part of the museum would be kept open.

She said: "Currently, under a third of staff who work weekends at National Museums Scotland receive weekend payments.

"These payments have not been, and are not being, withdrawn from these staff, who were all employed before 2011.

"PCS is, however, demanding the introduction of weekend payments for all staff who work weekends.

"This would cost the public purse over £420,000 each year. This is not affordable, following significant cuts to our government grant over the past 10 years and the challenge of a further cash cut which we face from April 1."