Following in his mother Princess Diana's footsteps, Prince Harry visited the deadly minefields of Angola and revealed his irritation that governments that supplied the devices had not done more to clear them.

Harry visited the town of Cuito Cuanavale, the most densely mined in Africa, with the Halo Trust charity, the oldest of its kind, which has been working to remove landmines planted during the country's vicious civil war, which raged until 2002.

Princess Diana made headlines around the world shortly before her death in 1997 when she visited Angolan minefields to raise awareness of the plight of the thousands of civilians maimed or killed by the devices.

Prince Harry is the charity's 25<sup>th anniversary appeal patron, and witnessed the organisation's ongoing efforts.

"Landmine accidents occur when people inadvertently wander into a minefield or are forced to take the risk of travelling through a minefield in order to collect water, fetch firewood or grow food for their families," reads the charity's website.

"Anti-tank mines on roads deny vehicular access to entire areas and strike unexpectedly causing multiple casualties. They disrupt equally the movement of people and goods, civilians and military, aid organisations and the government."

Despite clearing 21,300 mines since 2002, and rendering the province of Huambo mine free, the Halo Trust estimated that it could take up to 19 more years to remove the remaining devices.

Its chief executive Guy Willoughby told the BBC: "He [the prince] is irritated about the countries that supplied these landmines are not actually putting in any funds to clear them 25 years later.

"He has got quite a bee in his bonnet about that, and that is good.

"The commitment shown by Prince Harry plays an invaluable role in helping us to raise awareness of Halo's work and mission.

"He is technically very competent but he's also very good with dealing with the people, the villagers, the de-miners and he understands the big issue, even the political issue.

"Wars may be over but many people are still unable to resume their normal lives, facing the threat of death or injury by landmines every day."

He told BBC News that being able to support the charity was "hugely important" to Prince Harry, not just because of the family connection.

"As a soldier he is seeing so many people of his generation, of his age losing limbs. And that has really brought a focus on it.

"I think it has brought a focus on it for a lot of the British population of seeing so many people in their 20s who are losing limbs."

China and Romania are both known to supply landmines, and US and Italian manufacturers are believed to have secret supply contracts.

The Angolan civil war raged for 26 years, left an estimated 500,000 dead and displaced four million people, as well as destroying much of the country's infrastructure.

Prince Harry was criticised for meeting Angolan vice-president Manuel Vicente as part of the visit, with criminal complaints being filed against the former oil executive days before for "illegal" business deals relating to his role with a leading Chinese company seeking Angolan government contracts.

Kensington Palace described the visit as a "courtesy call".