Cambodia's retired king has called on the country's leaders to release an opposition lawmaker from jail and to welcome back two others who fled the country fearing arrest. But, the government says the matter is out of its hands.

Former King Norodom Sihanouk on Thursday posted an open letter on his Website to his son, Prince Norodom Ranariddh, and to Prime Minister Hun Sen, asking them to restore the parliamentary immunity of three opposition lawmakers in order to open the door to national reconciliation.

On February 3, Cambodia's legislature stripped the immunity of opposition leader Sam Rainsy and his deputies, Cheam Channy and Chea Poch, leaving them vulnerable to lawsuits from the prime minister and the prince, who is president of the National Assembly.

Cheam Channy was arrested, while Sam Rainsy and Chea Poch fled to the United States, where they are seeking support from U.S. officials and members of the Cambodian-American community.

Writing from Beijing, the former king said the leaders should remove threats of legal action against the three, and accept the presence of an opposition party. He said he wrote the letter after he and his successor, King Norodom Sihamoni, received international criticism for not intervening in what he called a "political tragedy."

However, government spokesman Khieu Kanharith says any decision to restore the lawmakers' immunity will have to come from the country's courts.

"Only two person can decide it: one, Prince Ranariddh, who is the victim of this accusation; two, the court," said Khieu Kanharith. "Not the government and not the National Assembly."

Sam Rainsy and Chea Poch face defamation suits from Prince Ranariddh, who is also president of the Funcinpec Party, after accusing him of accepting bribes to form a coalition government with the Cambodian People's Party. Sam Rainsy also faces a libel suit by the prime minister for alleging that the government planned to kill political figures last year.

Cheam Channy was arrested after losing his immunity and now sits in jail accused by the government of leading a shadow army. He claims he simply headed a group that was overseeing military activities.

Norodom Sihanouk said King Sihamoni should pardon Cheam Channy. He called on all sides to drop their lawsuits.