LONDON: A rare oil painting of Indian independence leader Mahatma Gandhi, which is believed to have been damaged by a Hindu nationalist activist, is to be auctioned in London in July.

Gandhi, one of the most influential figures in India’s history, led a non-violent movement against British rule and inspired similar resistance campaigns across the world.

He is the subject of tens of thousands of artworks, books and films.

But a 1931 painting by British-American artist Clare Leighton is believed to be the only oil portrait he sat for, according to the painter’s family and Bonhams, where it will be auctioned online from July 7 to 15.

“Not only is this a rare work by Clare Leighton, who is mainly known for her wood engravings, it is also thought to be the only oil painting of Mahatma Gandhi which he sat for,” said Rhyanon Demery, Bonhams Head of Sale for Travel and Exploration.

The painting is a “likely hidden treasure,” Caspar Leighton, the artist’s great-nephew, told AFP.

Going under the hammer for the first time next month, the painting is estimated to sell for between £50,000 and £70,000 ($68,000 and $95,000).

Clare Leighton met Gandhi in 1931, when he was in London for talks with the British government on India’s political future.

She was part of London’s left-wing artistic circles and was introduced to Gandhi by her partner, journalist Henry Noel Brailsford.

“I think there was clearly a bit of artistic intellectual courtship that went on,” said Caspar, pointing out that his great-aunt and Gandhi shared a “sense of social justice.”

The portrait, painted at a crucial time for India’s independence struggle, “shows Gandhi at the height of his power,” added Caspar.

It was exhibited in London in November 1931, following which Gandhi’s personal secretary, Mahadev Desai, wrote to Clare: “It was such a pleasure to have had you here for many mornings doing Mr.Gandhi’s portrait.”

“Many of my friends who saw it in the Albany Gallery said to me that it was a good likeness,” reads a copy of the letter attached to the painting’s backing board.

The painting intimately captures Gandhi’s likeness but it also bears reminders of his violent death.

Gandhi was shot at point-blank range in 1948 by disgruntled Hindu nationalist activist Nathuram Godse, once closely associated with the right-wing paramilitary organization RSS.

Godse and some other Hindu nationalist figures accused Gandhi of betraying Hindus by agreeing to the partition of India and the creation of Muslim-majority Pakistan.

According to Leighton’s family, the painting was attacked with a knife by a “Hindu extremist” believed to be an RSS activist, in the early 1970s.

Although there is no documentation of the attack, a label on the back of the painting confirms that it was restored in the United States in 1974.

Under UV light, Demery pointed out the shadow of a deep gash running across Gandhi’s face where the now-restored painting was damaged.

“It feels very deliberate,” she said.

The repairs “add to the value of the picture in a sense... to its place in history, that Gandhi was again attacked figuratively many decades after his death,” said Caspar.

The only other recorded public display of the painting was in 1978 at a Boston Public Library exhibition of Clare Leighton’s work.

After Clare’s death, the artwork passed down to Caspar’s father and then to him.

“There’s my family’s story but the story in this portrait is so much greater,” he said.

“It’s a story for millions of people across the world,” he added.

“I think it’d be great if it got seen by more people. Maybe it should go back to India — maybe that’s its real home.”

Unlike countless depictions of the man known in India as the “father of the nation” — in stamps, busts, paraphernalia and recreated artwork — “this is actually from the time,” said Caspar.

“This might be really the last truly significant picture of Gandhi to emerge from that time.”