Twenty years after Prince Harry’s mother helped bring the lethal scourge of landmines to global attention, the government has pledged £100m to the campaign supported by the prince to make the world landmine-free by 2025.

The international development secretary, Priti Patel, announced that the UK was tripling its backing for de-mining as she addressed a Kensington Palace reception, hosted by Harry, on International Mine Awareness Day.

Just months before her death in a Paris car crash in 1997, the striking image of Diana, Princess of Wales, wearing a protective visor and vest and walking through an Angolan minefield, highlighted the work by the Halo Trust. Her last overseas tour was to Bosnia in August 1997 when she met victims of the weapons.

Harry continues to champion the cause as patron of the Halo Trust.



Facebook Twitter Pinterest Princess Diana walking through a minefield in Angola in 1997. Photograph: John Stillwell/PA

Speaking at the reception, Patel said the funding, over three years, would be used to make safe the equivalent of more than 20,000 football pitches and help free 800,000 people from the threat of mines.



She highlighted the efforts by the late princess in bringing landmines to the world’s attention, describing her as “courageous”.



Diana’s campaigning and her call for an international ban on the devices during her Angolan visit led to the then junior defence minister Earl Howe calling her “ill-informed” and a “loose cannon that Her Majesty’s government did not need”.



Marking her contribution, Patel said: “We are here tonight because we recognise that landmines are a global scourge that must be tackled. Global Britain has a historic role in tackling the indiscriminate and lethal legacy of landmines. That role was, of course, embodied by the efforts of His Royal Highness’s late mother, Diana, Princess of Wales.”



The reception commemorates the 20th anniversary of the anti-personnel mine ban treaty, signed in 1997 by 128 countries to forbid the use and production of the weapons. Nearly 30 countries have been declared mine-free in the past 20 years, but more than 60 million people are estimated to still live with the daily fear of unexploded munitions, according to campaigners.



Harry said his mother’s work on banning landmines in the last months of her life “wasn’t universally popular. Some believed she had stepped over the line into the arena of political campaigning – but for her this wasn’t about politics; it was about people,” he said.

He added: “She knew she had a big spotlight to shine, and she used it to bring attention on the people that others had forgotten, ignored or were too afraid to support.” He said his mother, were she here today, “wouldn’t be willing to accept any credit” for the Ottawa treaty signed by 122 states in the year of her visit to Bosnia and Angola.

Harry said Diana had met two young boys who had lost legs to landmines in Bosnia. Introducing them, he added: “Those two young boys, Malic and Žarko, are now grown men and are with us today. 20 years on, they both still struggle with their physical and emotional injuries and with the high costs of replacing their prosthetics.

“When my mother said goodbye to Žarko that August, just weeks before her untimely death, she told him he would not be forgotten. Please help me keep her word to Žarko and Malic, and other people like them throughout the world, who still need us to finish the job and rid the planet of landmines. Collectively we have the knowledge, skill, and resources to achieve it, so let’s make future generations proud and finish what we started.”

A Kensington Palace spokesman said: “In the year marking the 20th anniversary of the princess’s death, Prince Harry is pleased to have this moment to recognise the significant contribution his mother made in this field, the progress which has been made by MAG [the Mines Advisory Group], Halo, the UK government and other organisations, and the opportunity to continue raising awareness of making the world landmine-free by 2025.”



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James Cowan, the Halo Trust chief executive, said: “Tonight, as we remember the work that was done by Diana, Princess of Wales, and others two decades ago, an historic opportunity is presented to unite government, corporate and private donors and mark the start of a countdown to a mine-free world. As with the eradication of smallpox, a mine-free world is not a pipe dream but a real possibility, but only with the right financial support.”



Jane Cocking, the chief executive of MAG, said: “Nearly 40% of people injured or killed by landmines every year are children, who often fall victim when innocently playing or travelling to and from school. Twenty years on from the landmark mine ban treaty, these indiscriminate weapons still blight the lives of far too many people around the world. Yet, with the sort of commitment and ambition shown today, ridding the world of this problem is far from impossible.



“If other donors follow the UK’s lead in recommitting to support the vital job of landmine clearance, the goal set by treaty signatories of a landmine-free world by 2025 is totally achievable.”

