France on Wednesday warned Cambodia not to take any action without a clear legal basis after a French architect with ties to disgraced Chinese politician Bo Xilai was arrested in the country.
"We have asked Cambodian authorities for clarifications on the motives for his arrest," French foreign ministry spokesman Bernard Valero said.
"We have made clear that we will be watchful that no legal action of any kind be brought against him unless its legal basis has been clearly established."
The French embassy in Cambodia said Tuesday that Patrick Devillers had been arrested, in a new twist to China's biggest political scandal in decades.
Cambodian police said the arrest was carried out with the cooperation of Beijing, which is seeking his extradition.
"We are following this case very closely and providing consular protection," Valero said. "The consul visited him immediately have his arrest and continues to do so each day."
Devillers is understood to have been a close business associate and friend of Bo and his wife Gu Kailai.
Bo, the former leader of the southwestern Chinese megacity of Chongqing, is being probed for corruption while Gu has been detained for suspected involvement in the murder of British businessman Neil Heywood last year.
The scandal surrounding Bo and Gu, which first came to light in February and made worldwide headlines, has exposed deep divisions within the Communist Party ahead of a crucial, once-in-a-decade leadership transition, analysts say.