Ten years after the death of Princess Diana and the first global treaty against antipersonnel landmines, experts say only a handful of rebel groups and perhaps one state dare use what has become a pariah weapon.

Hard to detect, difficult to clear and often designed to maim rather than kill, antipersonnel mines can linger in the soil for decades. Activists estimate mines still kill or injure perhaps 15,000 to 20,000 people a year -- mainly civilians in countries now at peace.

Landmine clearance agencies say it will likely take another decade to clear probably the world's two most affected countries -- Angola in southern Africa and Cambodia in Southeast Asia -- both the scene of long-running but now ended civil wars. Ongoing conflicts delay clearance in Iraq, Afghanistan and elsewhere.

But fewer are now being laid and many activists have moved on to a campaign against cluster munitions in the aftermath of last year's Lebanon war, which left much of the country's south seeded with small unexploded bomblets.

"There is a global stigma attached to landmines now," said Paul Hannon, executive director of pressure group Mines Action Canada.

"The supply of mines is drying up. I wouldn't say we have won the war but we have won the battles so far. We have to stop people slipping back and we have to get the mines out of the ground."

Activists say global opinion was already turning against antipersonnel mines even before Diana, Princess of Wales, began using her fame to draw attention to the issue. But they say her campaigning sped up the process.

Diana joined a British Red Cross campaign against landmines in 1997 and before she died visited Angola and Bosnia with landmine charities.

"I don't know whether individuals change history that much or whether landmines had simply had their day," said Simon Conway, director of British-based group Landmine Action. "But everyone remembers those pictures of Diana in the minefields and when it is someone as iconic as that it makes a difference."


RUSSIA, NEPAL STOP

Campaigners say the focus on the issue at the time of Diana's death in a Paris car crash in August 1997 almost certainly boosted the number of countries that signed the Ottawa treaty banning antipersonnel mines a month later.

Eighty percent of countries have now signed.

Non-Ottawa signatories the United States, China and Russia continue to hold millions of antipersonnel mines between them -- but now seem not to use them.

The 2006 Landmine Monitor report -- regarded as the most authoritative and edited by Mines Action Canada -- labelled three states as using antipersonnel mines.

It accused Russia of using them in its war on Chechen separatists, Nepal in its fight against Maoists and Myanmar -- also known as Burma -- against internal rebels, who were also using them.

But Mines Action Canada's Hannon told Reuters Russia appeared to have since stopped, while a peace deal in Nepal halted both government and Maoist minelaying.

That left Myanmar as the only proven state user in 2007.

Renewed civil war in Sri Lanka in 2006 had involved some new antipersonnel minefields, he said, most apparently laid by Tamil Tiger rebels. There were suggestions the government might also have laid mines but little hard evidence, he said. Also, mine use was much more limited than in earlier stages of the war.

Other non-state groups in a few countries from Colombia to Somalia were also using antipersonnel mines, he said. But even that was falling off.


STILL EFFECTIVE?

Some other countries retained existing minefields -- most notably the vast, heavily mined demilitarised zone between North and South Korea -- without adding to them.

Larger anti-tank and anti-vehicle mines -- not banned by Ottawa -- also seemed to be used less, Hannon said; although it was hard to tell why and there might be a new spike of use in Afghanistan.

Some experts say there is less of a role for fixed minefields as recent conflicts have fewer fixed positions and mass infantry clashes -- and modern militaries can break through minefields relatively easily.

Others say they remain an effective way of slowing an invading force and governments could swiftly switch back to using them. The slowness with which they are being cleared from the world proves they work, they warn.

"Landmine warfare is not over," said one British demining specialist. "They are very effective weapons. They are not as easy to get hold of as they used to be but they are very cheap to produce."