Harsh new trade tariffs imposed on Cambodia by US President Donald Trump are "not reasonable", the Southeast Asian country's commerce ministry said Thursday.

Cambodia was among the nations hardest hit by Trump's swinging "Liberation Day" tariffs, singled out for a 49 percent levy.

Trump's latest salvos -- against friends and foes alike -- rattled stock markets and alarmed governments around the world.

Penn Sovicheat, a Cambodian commerce ministry spokesman, told AFP the harsh US tariffs on his country were "not reasonable".

Cambodia had about $10 billion in exports to the United States last year, mainly garment products, he said, while American imports came to around $264 million, taxed at average of 29.4 percent. 

"The 49 percent tariffs is not a good image for Cambodian industry or our investment attraction," he said.

He said the government is studying the matter carefully and hopes to negotiate with Washington via existing mechanisms such as the ASEAN grouping or via the World Trade Organization. 

Cambodia is a major manufacturer of low-cost clothing for big Western brands, but at a press briefing, a White House official accused the kingdom of being a front for Chinese-made goods.

"China has turned Cambodia into the most important transshipment hub that Communist China uses to evade our tariffs," the official said.

In an interview on state-run TV, Commerce Minister Cham Nimul warned that US consumers would be the first to be affected by the tariffs. 

"The increase in tariffs means that the US people who make the purchase orders of Cambodian products are the first people to be impacted and next will be Cambodia and business people," she said