LONDON: Twenty years after Princess Diana's iconic visit to a minefield in Angola, the world faces a new landmine crisis in Syria and Iraq on a scale not seen for decades, campaigners said on Sunday.

The Mines Advisory Group said it had cleared and destroyed more than 9,000 newly laid landmines in both countries in the past six months in areas formerly occupied by the Islamic State militant group.

Jane Cocking, the group's chief executive, said at least $100 million of additional funding will be needed per year to tackle both newly laid land mines and those still in the soil from previous conflicts in more than 60 countries.

"The problem is that we're seeing the emergence of a new crisis of a scale that we haven't seen since the 1990s, and to deal with that as well requires substantially more money," Cocking told the Thomson Reuters Foundation.

It is hard to gauge the scale of the problem, she said, but judging by the number of mines already cleared, Islamic State has produced improvised landmines on an "industrial scale".

Production and use of landmines has declined after the Mine Ban Treaty, which prohibits their use, stock piling and transfer, was adopted nearly two decades ago.

Hard to detect, difficult to clear and often designed to maim rather than kill, landmines can linger in the soil for decades and kill or injure thousands of people every year.

Cambodia, Sri Lanka, Angola and Afghanistan are among the most mined countries in the world, according to the Landmine Monitor, the most authoritative source on the issue.

MORE WORK TO DO

Images of Princess Diana walking through a minefield in Angola 20 years ago this weekend helped raise global awareness of landmines and the plight of their victims.

About seven months later Princess Diana, who had divorced heir-to-the-throne Prince Charles in 1996, died from injuries sustained in a car crash in Paris.

More than 160 countries have signed the Mine Ban Treaty and 27 countries and one territory have declared themselves free of landmines, including Mozambique after a 20-year mine-clearing programme, and Rwanda and Nicaragua.

The number of people reported killed or injured by landmines has risen sharply though, with 75 percent more casualties in 2015 compared to the previous year, according to the Landmine Monitor. Many of them were civilians.

This was largely due to more victims in Libya, Syria, Ukraine and Yemen, but also due to improved availability in casualty data, the Monitor said in its most recent report in November 2016.

"There has been a lot of progress but a lot of work still needs to be done, in particular because we now face a new toxic mix in countries like Iraq, Syria and Libya," said James Cowan, chief executive of British charity The Halo Trust.Donors and affected states contributed some $471 million for landmine clearing in 2015, a 23 percent decrease from the previous year and the lowest level since 2005, according to the Landmine Monitor.

"There isn't enough money available for landmine clearance in general, so it makes it very difficult to deal with new landmine emergencies like the ones in Iraq and Syria," Cowan told the Thomson Reuters Foundation by phone from Angola.

Campaigners say a lack of funding puts the Mine Ban Treaty's proposed 2025 deadline for a mine-free world at risk.

"It requires political will and more money to finish the job," said Cocking.