The Southbank Centre has unveiled plans to transform the complex around the Queen Elizabeth Hall, the Purcell Room and the Hayward Gallery.
The proposals include the refurbishment of the existing 1960s buildings and the creation of a new glass pavilion and a central foyer.
More top news
The capital's theatres also generate more searches than those in any other city, according to research by Google.
Union officials are expected to meet next week to plan further stoppages if talks fail to resolve the dispute.
Natalie Sharp and Christine Bicknell appeared in court over an alleged incident at a Lidl superstore in Wallington, south London.