Graffiti on a wall in Winchester Square near Borough Market has been removed by Southwark Council as part of Capital Clean Up Week.
"We act on complaints received and remove the graffiti in a turn around time of 24 hours to create a cleaner environment for everyone.
"We acknowledge the interest and enthusiasm that currently exists for well-known artists' work.
"However, graffiti is illegal and it costs a good deal of taxpayers' money to clear it up, which could be spent on much more important things that would improve community life for all of us.
"The council takes a tough stance on all forms of antisocial behaviour, including graffiti, and we have a good track record of removing it very quickly."
The council says it spends an estimated £260,000 a year cleaning up graffiti – equivalent to the annual salary of eight teachers.
Councils and other landowners have sometimes been criticised for removing so-called street art. Network Rail came under fire last year for painting over work by Banksy in the grim Leake Street tunnel at Waterloo.