Cambodian politician and government critic Sourn Serey Ratha is escorted by police officers at the Municipal Court of Phnom Penh, Cambodia, August 14, 2017. REUTERS/Samrang Pring

PHNOM PENH (Reuters) - A critic of Cambodia’s government was charged on Monday over comments criticizing the deployment of troops to the border with Laos and Prime Minister Hun Sen threatened arrest for anyone suggesting he was using the border row to boost his popularity.

The spat with Cambodia’s neighbor lasted barely 24 hours last week before Laos pulled back soldiers well ahead of a deadline set by Hun Sen, who faces a challenge to his rule of more than three decades in an election next year.

Sourn Serey Ratha, head of the minor opposition Khmer Power Party, was charged with inciting soldiers not to obey orders, incitement to commit a crime and discouraging soldiers over comments in a Facebook post.

Deputy Prosecutor Ly Sophana told reporters the Phnom Penh Municipal Court had decided the comment “affected national security” and was dangerous for national defense.

In a Facebook post on Aug. 12, Sourn Serey Ratha called Cambodia’s military leaders “thieves” who would sleep in air conditioned rooms and enjoy time with girls while leaving their men to get killed if there were a skirmish with Laos.

Opponents of Hun Sen, one of Asia’s longest serving rulers, accuse the former Khmer Rouge guerrilla of using all measures he can to silence critics and undermine the opposition ahead of the general election.

In a speech at a university graduation ceremony on Monday, Hun Sen said Sourn Serey Ratha’s comments had been unacceptable and he was better off in prison so the army would not “cause trouble” for him every day.

Hun Sen said anyone accusing him of using the border dispute with Laos to boost his popularity would be arrested.

“Don’t call me a dictator. A democratic country without the rule of law is just anarchy,” he said.