Beijing: A top Chinese government diplomat says foreigners should not interfere in Cambodia's internal affairs after an election was broadly criticised as being neither free nor fair.

China is Cambodia's most important diplomatic and economic backer.

Cambodian Prime Minister Hun Sen Credit:AP

Prime Minister Hun Sen's ruling Cambodian People's Party on Monday said it had won all 125 parliamentary seats up for grabs in a general election a day earlier, a vote heavily criticised by rights groups, the United States and other Western countries.

Chinese State Councillor Wang Yi offered his congratulations for what he said was a "smooth" election, China's Foreign Ministry said in a statement late on Wednesday after Wang met Cambodian Foreign Minister Prak Sokhon on the sidelines of a regional forum in Singapore.