Street artist Banksy has confirmed he is behind the artwork which shows shady agents eavesdropping around a telephone box on a street in Cheltenham, Gloucestershire.
The piece appeared three miles from GCHQ, home of the Government's spying network, leading many to speculate that the artist is taking a swipe at the UK's intelligence-gathering methods.
The mural shows three 1950s-style agents, wearing brown trench coats and trilby hats, using devices to tap into conversations at a telephone box.
The Bristol artist did not officially confirm the piece at the time but claimed responsibility during a question and answer session on his website.
Banksy was asked four questions on his website, including, "Did you paint the spies in Cheltenham?" to which he replied: "Yes".
In reply to another question the artist said the worst thing about street art is: "Having to make your mistakes in public".