Olivier award-winning actor Bertie Carvel is leading a campaign aimed at preventing performers having to work two shows on a Sunday.

Equity and the Society of London Theatre’s proposed settlement for the West End in 2013 currently includes a clause that would allow two Sunday performances.

At the moment, productions are only allowed to have one Sunday performance, with an extra one through negotiation with a show’s company.

Thriller Live in the West End currently has two shows on a Sunday, while other productions are understood to have tried a second show but struggled to attract high attendance figures.

This means that, even if the settlement is approved as it is currently proposed, producers would not necessarily take up the option of introducing a second Sunday show in the evening.

However, Carvel, who won an Olivier for his role of Miss Trunchbull in Matilda, has used social networking site Twitter to urge performers to reject the proposed settlement.

He said performers who have children and who may have to work two Sunday shows would become “absentee parents”.

In another tweet, he said: “Five-show weekends will become the norm and ruin family life unless we reject the West End settlement.”

Equity declined to comment while a ballot of its members is being carried out. This will close on Friday (March 15).

However, in Equity’s proposal document, Hilary Hadley, head of the live performance department at the union, recommends the settlement to members.

She explains that negotiations have been “tough and prolonged” and adds that the overall settlement for 2013 will give West End employees a 2.2% increase, which she calls “0.8% short of our ambition”.

From January next year, there is a proposed, further increase of 2%.

She states that if the settlement is rejected “there will be no more money on offer”.

She adds: “The agreement is for a two-year period only. This means that both sides will be able to monitor how it is working in practice. We will be able to claim again, on the basis of real experience, in 2014.”