Video report by ITV News Royal Editor Chris Ship
A campaign to rid the world of landmines by 2025 - supported by Prince Harry - is to receive a £100 million boost from the government.
The UK is set to triple its contribution for demining, International Development Secretary Priti Patel announced on Tuesday.
Ms Patel described mines as a "global scourge" that must be tackled.
The move was revealed at Kensington Palace and coincides with International Mine Awareness Day.
Ms Patel said the funding would be used to make safe the equivalent of more than 20,000 football pitches and help 800,000 people live their lives free from the threat of mines.
Ms Patel also highlighted the efforts made by Prince Harry's mother Diana in bringing landmines to the world's attention 20 years ago, describing her as "courageous".
At the time the Princess's campaigning caused great controversy.
Just months before she died in a car crash in 1997 the Princess walked through an Angolan mine field being cleared by the HALO Trust.
Diana's last overseas tour was to Bosnia in August 1997 when she met victims of the weapons.
Prince Harry, who gave the keynote address at the Kensington Palace reception, is continuing to champion his mother's cause just months ahead of the 20th anniversary of her death.
"We are here tonight because we recognise that landmines are a global scourge that must be tackled," Ms Patel said.
She added: "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' late Mother, Diana, Princess of Wales."
Speaking on Tuesday evening, Prince Harry said: "When [my mother visited Bosnia in August 1997] she met two young boys – one Muslim, one Serbian – who had both lost legs to landmines. She shared their stories with the world, and helped campaigners... to change history.
"Those two young boys, Malic and Žarko, are now grown men.
"Twenty 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."