Cambodian premier Hun Sen punched back in a diplomatic spat with Washington on Friday by halting cooperation with a US project to recover the remains of American soldiers killed during the Vietnam war.
The move is the latest in a tit-for-tat battle that has seen relations sour dramatically in recent weeks amid Hun Sen's accusations that the US assisted an opposition leader with a treason plot.
Hun Sen said his suspension of the search for missing-in-action soldiers was retaliation for the US's announcement this week that it would stop issuing visas to senior Cambodian foreign ministry officials and their families.
That move was a reprisal for Cambodia's refusal to take in Cambodian nationals deported from the US for committing crimes.
"In response, Cambodia tells the US that its cooperation with finding the remains of Americans missing in Cambodia... is suspended temporarily," Hun Sen said Friday in a speech.
"You do to me, I also do to you," he added.
The strongman said Cambodia wanted to renegotiate the deportation deal, which has seen more than 500 Cambodians forcibly ejected from the United States since 2002.
Critics say the agreement cruelly splits up families and is a form of double punishment for deportees, who have already served jail time in the US and often have thin links to Cambodia.
Hun Sen said he would resume cooperating in the search for missing American soldiers once the US lifts its visa ban, which was also issued against three other countries.
The US defense department's search program has recovered the remains of 42 American servicemen in Cambodia, but 48 others are still unaccounted for.
The Vietnam War remains a sensitive topic between the two nations, with Hun Sen frequently citing America's secret bombing campaign in Cambodia in his tirades against the United States.
After the war Washington went on to become one of Cambodia's biggest donors, helping the kingdom rebuild from the atrocities of the Khmer Rouge regime.
But Washington's influence in the fragile democracy -- dominated by Hun Sen for 32 years -- has steadily withered amid China's rising dominance in the region.
Beijing has pulled Hun Sen into its orbit with massive aid and investment deals that come without the kind of pressure that other donors often demand to improve human rights or uphold democratic principles.
On Tuesday, US Ambassador William Heidt warned that Cambodia's democracy was in peril after this month's arrest of the opposition leader Kem Sokha, the latest in a protracted government crackdown on Hun Sen's critics.
The ambassador vehemently denied the "absurd" allegation that the US had assisted Kem Sokha with a treason plot, calling it "inaccurate, misleading and baseless".