Chorus members of the Welsh National Opera (WNO) are to stage a series of strikes in a dispute over jobs and pay.
Equity said the walkouts will hit a number of productions in the coming weeks.
Strikes will be held on September 21 (the opening night of Rigoletto) and 29 (Il Trittico) and October 11 (Opera Favourites At The Movies).
Other forms of industrial action will be held from September 21 to December 6.
The announcement of strike action follows a 93% yes vote in a ballot of chorus members.
Equity said WNO management has proposed to cut the size and hours of the chorus, with singers facing a 15% pay cut and the threat of compulsory redundancies.
Paul W Fleming, Equity general secretary, said: “Taking strike action is unprecedented among the Welsh National Opera chorus and it’s not a decision taken lightly.
“Singers are not prepared to be cast aside in management proposals which would catastrophically harm this Welsh cultural icon.
“WNO needs to realise that the chorus is a key asset and come to the negotiating table so we can agree a way forwards that works for the WNO, the chorus and future productions.”
A WNO spokesperson said: “While we respect the right to strike by Equity members in WNO Chorus we are disappointed that this will mean our audiences will potentially miss out due to the impact on performances/concerts.
“WNO have a planned meeting next week with union representatives to progress negotiations and discuss new proposals, while also recognising the reality of WNO’s financial situation following significant cuts to our public funding.
“We continue to do everything we can to avert strike action in order to perform our full autumn season as planned.”
