Demining worldwide has been undermined by a sharp drop in funding, and Cambodia is among more than a dozen countries which will likely fail to meet their mine clearance targets as donor money dries up.
The government's demining agency, the Cambodian Mine Action Center (CMAC), has lost a fifth of its funding this year, director general Khem Sophoan said.
"CMAC alone spends US$10 million a year, but we can't secure that amount from donors," he said, adding that the international community contributes 95 percent of the agency's funding.
"If there are no funds, we cannot work," he said.
"It's difficult for us because the donors sometimes don't tell us why they withdraw their funds," he said.
Despite feverish demining efforts that began in the early 1990s, Cambodia remains littered with millions of landmines and other unexploded munitions that continue to kill or maim an average of two people each day.
In the aftermath of three decades of war, as many as 10 million landmines are still strewn through nearly 4,000km2 of forest and rice field in the country's mostly northwestern provinces.
Funding for demining in Cambodia last year totaled some US$25.6 million, including government contributions, a significant decrease from 2004 when US$41.7 million was pledged for mine clearance, according to the International Campaign to Ban Landmines.