Defacing Rothko painting 'not vandalism' Published duration 8 October 2012

media caption Speaking the day after the incident, Vladimir Umanets told the BBC he did not 'deface' the painting

A man who claims responsibility for defacing a painting by Mark Rothko at the Tate Modern has told the BBC: "I'm not a vandal."

The painting, Black on Maroon, one of Rothko's Seagram murals, was written on with black paint on Sunday.

Vladimir Umanets, founder of a movement he calls Yellowism, claims to be responsible but denies criminal damage.

Police are yet to arrest anyone in connection with the incident in the central London gallery.

Works by the modernist US painter have sold for tens of millions of pounds.

Speaking to the BBC, Mr Umanets compared himself with the surrealist artist Marcel Duchamp.

He said: "Art allows us to take what someone's done and put a new message on it."

He said the most contemporary thing to do now was to "abandon and live art" and that he hoped he would "be considered as someone who really creates".

However, he acknowledged he was likely to be arrested shortly.

"I'm expecting this - I'm not interested in spending time in prison but if I have to... I have no lawyer, I don't have the money."

He added that he was a big fan of Rothko.

"Rothko is such a powerful artist. There will never be another Rothko in the world ever.

"I would like to show such a wonderful piece in the context of Yellowism."

After the incident, Tate Modern was shut for a short period.

But a spokesperson for the gallery told BBC arts correspondent Will Gompertz that it would not change its policy of allowing people up close to the art.

'Quick exit'

On Twitter , eyewitness Tim Wright said: "This guy calmly walked up, took out a marker pen and tagged it. Surreal.

"We gave a description to the gallery. Very bizarre. He sat there for a while then just went for it and made a quick exit."

Mr Wright later uploaded a picture to Twitter which showed five or six words on the bottom-right corner of the painting with black streaks of paint running down from the daubed writing.

They appear to read: "Vladimir Umanets, A Potential Piece of Yellowism."

A Tate spokeswoman said: "Tate can confirm that there was an incident in which a visitor defaced one of Rothko's Seagram murals by applying a small area of black paint with a brush to the painting."

Conservator Julia Nagle said on Radio 4's Today programme that she had "every faith" the defaced painting could be restored.

"The first thing you need to know is what the painting was originally made of, in order to distinguish between the solubility of what you want to get rid of and the original painting.

"Fortunately, in the case of Rothko, there's a massive body of research into his techniques - and a great conservation department at Tate."

She added the graffiti would be "much more soluble because it is newer", meaning damage to the existing layers would be unlikely.

Chief art critic at The Times Rachel Campbell-Johnston told the BBC it would be a shame if security was changed in the light of the Rothko event.

"I really, really feel it's important people feel they can have a one-to-one connection (with the artwork)," she said.

"If you up security, you destroy the connection people can get."

She added: "Galleries have very good security, it's just a very sad thing someone had to do this but we can't have armed police in galleries."

Russian-born Rothko emigrated to the US at the age of 10, and went on to become an important post-war abstract expressionist.

He was commissioned to paint the Seagram murals in 1958 for Manhattan's Four Seasons restaurant, but they were never installed.

Shortly before his death in 1970, he presented some of the murals to the Tate Gallery.