A tree mural in Finsbury Park that appeared overnight on a residential building is the work of Banksy, the anonymous street artist has confirmed.

The artist claimed ownership of the graffiti in an Instagram post on Monday, after it had been the subject of speculation for a morning since it appeared on the building in Hornsey Road.

The artwork shows green areas behind a trimmed tree, which are intended to give the appearance of leaves. Next to it is a stencil of a person holding a high-pressure hose.

The artwork appeared on Hornsey Road on Sunday.

Local residents said they were “proud and delighted” that the elusive artist chose their street for his latest mural.

Hornsey Road resident Wanja Sellers, who lives just a few doors down from the mural, said: “We are so proud and delighted that Banksy chose our street and Finsbury Park for his work.”

“The bright green tones represent beautiful Islington and of course St Patrick’s Day, which is beautiful and festive.”

“Choosing the colors of our district feels like a personal message to us residents. We are just so proud.”

By Monday morning, speculation had grown that the work was by Banksy before it was confirmed, with one expert saying it seemed a “dead certainty.”

Speaking to the BBC, documentary filmmaker James Peak, creator of the Radio 4 series The Banksy Story, said: “In my opinion, this looks like a surefire thing.”

He added: “It’s spring now and this tree should be full of leaves, but Banksy must have ridden past on his bike and thought how pathetic it looks.

“So on St Patrick’s Day he took exactly the same shade of green that Islington Council uses for its street signs and, using a high-pressure hose or fire extinguisher, sprayed the leaves back onto the rather dilapidated wall behind it.”

Islington councillor Flora Williamson also came across the artwork while door-to-door campaigning.

She later tweeted: “By far the most exciting thing about today’s doorstep campaigning session on Hornsey Road was seeing that Banksy had come to Tollington overnight.

“Lots of local interest – I’m a fan of it.”

Local residents have also posted about the mural on social media, with one saying: “Banksy came overnight and now my rent is going to skyrocket.”

Another added: “Proud of the new custodians of an apparently new Banksy work in Finsbury Park… Woke up this morning to see it on the side of a flat.”

Before this piece, his last confirmed work was in December, when he painted military drones on a stop sign in Peckham.

The work was removed less than an hour after its authenticity was confirmed on the artist’s social media. Witnesses reported that it was removed by a man with bolt cutters.

Two men were later arrested on suspicion of theft and property damage.