Song Kosal was just five when she lost her right leg to a landmine. But the tragedy inspired her to become one of Cambodia's most outspoken anti-mine campaigners, and even take part in a beauty contest.

Now 27, Kosal will share her dream of a "mine-free world" when she gives the opening address to delegates from more than 100 countries at a conference in Phnom Penh this week taking stock of a global ban on the weapons.

"I have dreamed many times that I still have two legs, but then I wake up," Kosal told AFP. "I don't want to see other people, children especially, to be hurt by landmines like me."

Representatives from the states that have signed the 1997 Anti-Personnel Mine Ban Convention will discuss progress on eradicating the weapons at the meeting that starts on Monday.

The meeting follows a report just days ago saying that global landmine use is at a seven-year high.

The International Campaign to Ban Landmines (ICBL) said that landmines and explosive remnants of war caused 4,191 new casualties in 2010, including more than 1,000 deaths.

Nearly three decades of civil war have left impoverished Cambodia one of the world's most heavily mined countries. Mines kill people there almost weekly, with 32 deaths recorded in the first nine months of 2011.

Before she became adept at moving around with a crutch, Kosal said, she felt "lonely, disappointed because I have only one leg and I could see other children running, playing".

Since then, she has blossomed, becoming a youth ambassador for ICBL and travelling the world to urge governments to destroy mines and help survivors.

The ICBL won the Nobel Peace Prize in 1997 for its efforts towards the Ottawa Treaty banning the use, production, stockpiling and trade in anti-personnel landmines.

In 2009, in a further effort to raise awareness, Kosal entered the inaugural Miss Landmine Cambodia beauty pageant, but the event was controversially cancelled after the government decided it was in poor taste.

The contest still went ahead online, and Kosal can be seen smiling broadly in her competition photo, posing on a small boat wearing a tiara and purple summer dress.

"Everyone has the right to be beautiful," Kosal said. "Taking part was one way I could show I am brave enough to do anything, that after we become survivors, we don't become invisible."

Since 1992, around 700 square kilometres (270 square miles) have been cleared of mines and other ordnance in Cambodia, destroying nearly a million anti-personnel mines, according to UN data.

But Chum Bun Rong, secretary general of the Cambodian Mine Action and Victim Assistance Authority (CMAA), said that much more needed to be done.

"We can't develop the country if the landmines remain," he said, adding that Cambodia intends to clear another 650 square kilometres between 2010 and 2019, requiring $400-500 million.

"Even though many landmines were cleared, there are still a lot more under the ground, and thousands of survivors who really, really need help," Kosal said.

A big frustration is that the United States has yet to commit to the treaty, she said.

"How long will they have to review the policy?" she sighed, noting that more than 30 countries -- including India, Russia and China -- have yet to join.

"I'm grateful because the US gives a lot of support to mine clearance. But it's not enough. We still need them to sign because then a lot of countries will follow."

On a personal level, there is still progress to be made as well. For herself, Kosal said, she hopes to one day find a prosthetic leg that doesn't hurt her as much as models she has tried in the past.