Cambodia has dismissed accusations by an anti-corruption pressure group that Prime Minister Hun Sen and his family have amassed $200 million in business interests including some with links to land grabs and environmental destruction.
The accusations, in a report by the group Global Witness, comes during a period of rising political tension between the veteran prime minister and the opposition hoping to challenge his grip on power in local elections in 2017 and a general election in 2018.
Global Witness, in its report titled Hostile Takeover, said Hun Sen's family owns or partly controls companies with listed capital of more than $US200 million ($A266 million).
That is likely to be a fraction of the real fortunes they hold through shell companies and the use of nominee owners, the group said.
Government spokesman Phay Siphan derided the report by a group that has been investigating issues such as illegal logging in Cambodia for decades.
"It has no quality," Phay Siphan said.
"It is just accusations. The report is personal propaganda against Hun Sen, the elected prime minister."
Global Witness said the companies that Hun Sen's family held interests in had links to well-known global brands. The interests represented "undoubtedly just a fraction of the true value of the a family's business holdings".
The family's interests were concentrated in the energy sector, and included fuel retail chains, power plants and renewable energy projects, the group said.
"The domestic companies they are affiliated to have been accused of a litany of abuses, including the theft of land and natural resources, violence and intimidation against local populations and environmental devastation," it said.
"Huge network of secret deal-making, corruption and cronyism" has helped prop up Cambodia's self-styled strongman, who has led the country for more than three decades, the group said.
"The report should serve as a warning to foreign investors."
A senior member of the main opposition party, the Cambodia National Rescue Party, welcomed the publication of what he said were details of the family's wealth.
"We all knew it but nobody could really talk about it," party member of parliament Son Chhay said.
"Now it is all public."
Recently, Hun Sen has come under pressure from the European Union to end what it sees as judicial harassment of opposition politicians. The EU has threatened to review about half a billion dollars in aid if the harassment continues.
Hun Sen has for decades dismissed accusation of rights abuses and links to graft and nepotism, and he regularly shrugs off Western pressure for reform while building strong relations with China.
China was the largest foreign investor in the fast-growing economy in 2015, accounting for $US864 million of the $US4.44 billion flowing into the country.
