Musician Serena Kaos said she had stopped working as a full-time performer after losing access to regular busking locations.
“It’s a huge, huge cultural loss for not just the current musicians, but the musicians of the future, especially working-class ones that used to have this as one of the few possibilities of getting inside the craft,” she said.
Simeon Scheuber-Rush, the union’s London regional officer, said the closure had left amplified performers without a viable space.
“We’ve got the lovely Christmas market and unfortunately that Christmas market hasn’t incorporated the busking pitch,” he said.
“It has closed it as well. So we’ve now been left with a situation where there are no viable busking pitches for amplified busking.”
Ms Kaos added that busking is “such an important part” of London’s culture but that it is “slowly becoming non-existent”.