Empty theatre buildings nationwide have been covered in colourful messages of support, as they remain closed due to Covid-19 concerns.

The National Theatre in London has been wrapped in bright pink barrier tape, which reads "Missing Live Theatre".

The project, led by stage designers group Scene Change, also includes the Manchester Royal Exchange and Royal Lyceum Theatre Edinburgh.

As well as the Lyric Belfast, the Sherman Theatre in Cardiff and Theatre Royale Plymouth.

Job losses for casual staff

Venues have been shut since March, with many warning that they will go out of business in the coming months without support.

The art intervention was unveiled on the same day that the National Theatre confirmed 400 casual staff will soon lose their jobs.

"We have committed to paying our casual staff until the end of August, but very sadly due to the changes in the government Job Retention Scheme, we simply cannot afford to offer financial support beyond that point, when we won't be back performing as usual," a spokeswoman told the BBC.

She added they hoped "additional financial support from government may be forthcoming" to allow performing again "in a limited way" but said "it is set to be many months before it will be possible to perform to audiences at usual capacities, so regrettably a proportion of job losses are unavoidable".

'Rylance: People are in trouble'

Speaking to BBC News on Friday, Oscar-winning actor, writer and theatre director Sir Mark Rylance warned that 70% of venues could be closed by Christmas, meaning 290,000 jobs in the sector are at risk, with redundancies being made already.

Sir Mark, who also revealed he will reprise his role in Jerusalem next year at some point, stressed that theatres can't go back to usual, and they are going to have to change how they operate and what stories they tell in light of the Covid-19 pandemic.

"They are devastatingly badly affected," said Rylance.

"We have discovered that what the pandemic has brought to the surface too, is that 70% of the workers in theatre are freelance," he added. "They've not benefitted from any furlough scheme or any of the job retention schemes that the buildings and the permanent staff have benefitted from, so people are really in trouble, and they're going to be in more trouble in August and September."

In a statement, Scene Change declared: "This is a moment of reset in our industry and we believe the design community can be an essential part of the transformation that will see theatre buildings being reopened and the ways in which theatre can be reimagined,"

"As shapers of theatrical space through the use of people and place, our work is pivotal in connecting an entire ecosystem within the theatre industry. We are ideally positioned to be at the heart of any discussions about how theatre operates in the future."

The tapes will stay up for a week and then be taken to envelop other theatres.

Venues throughout London's West End will join in on Saturday, while The RSC, Sadler's Wells, Theatr Clwyd and Theatre Royal Stratford East will take part the following week, along with Sheffield Theatres, and the Ambassador Theatre Group.

'Places of great healing'

Tom Piper, one of the team behind the campaign, told the BBC's Colin Paterson the design was "inspired by the fact that the National Theatre was sort of wrapped with hazard warning tape it looked like a toxic sort of waste site".

"And we know that theatres are not toxic places, they are places of great healing, where people will come together with a sense of community and that's what we're all missing at the moment," added Piper, who also who helped create the 2014 sea of ceramic poppies outside the Tower of London.

He encouraged people to go along and see the outdoor "guerrilla" artwork for themselves, from a safe distance.

"It's a gesture of love for these buildings really and to highlight that they're empty, they need to be full of people," he said.

Last week, Culture Secretary Oliver Dowden published a five-stage plan for a "phased return", which will initially let performances take place outdoors, with indoors performances to follow later.

However, the roadmap for the return of live theatre and music was met with calls for financial support and a timetable for reopening, with many dismissing the plan as inadequate.