Yukanthor became an influential figure in Parisian society, where he was invited to many parties and dinners in which he expressed his views on French colonialism, even having to flee to Brussels at one point.

Yukanthor's accusations were that the freely asked and granted protectorate of Cambodia had become a complete French colonial administration, that Norodom was forced to give up his power at gunpoint in 1884, that he was treated terribly by a Frenchman named de Verneville who abused his power with his mistress, the Mi-Ruong, that the Norodom "dynasty reigned for 3,000 years and has always cared for its people", and that the Cambodian "had become to slave inside the whims of (French) administrators".

In the letter sent to Le Figaro, Yukanthor said that there were two types of Frenchmen, those in Metropolitan France and those in the colonies, that the French knew "nothing about the Cambodians and believe we are barbarians", that France wants to impose its civilization, but "my family has ruled over the Kingdom for thousands of years", that labor should not be a punishment for sins, that Buddhism made the King the father of the people and Cambodians form a united family, that "we have our 'slaves', but your workers have the freedom to starve", "you make an ostentatious display of items of destruction in universal exhibitions", and that when Norodom asked for French protection, he did not ask for administration or civilization.

King Norodom was heartbroken by what had happened to Yukanthor and his predecessor who traveled to France, Duong Chakr and retired to his palace in Phnom Penh.

But because of Yukanthor's fall-out with the French, the Governor General Doumer threatened to dethrone him, and although bitter and disappointed with Sisowath, he made him heir to the throne.