Cambodian Prime Minister Hun Sen has ordered police, immigration and aviation authorities to "use all ways and means" to prevent opposition leader Sam Rainsy from returning from exile, as he has pledged to do before elections in 2017 and 2018, RFA's Khmer Service learned on Friday. Sam Rainsy, president of the Cambodia National Rescue Party (CNRP), has been out of the country, living in France or traveling since November 2015, the latest of many stints in exile to avoid what supporters and analysts say is persecution at the hands of long-time strongman ruler Hun Sen. He has vowed to return to help the CNRP contest local elections set for 2017 and national elections scheduled for 2018, and recently reached out to King Norodom Sihamoni to seek a pardom for himself and other opposition figures convicted or jailed by a legal system controlled by Hun Sen. But there is no order for Sam Rainsy arrest. The order to ban Sam Rainsy from entry came in a letter circulated by the Council of Ministers ordering the General Department of Immigration to work with agencies including the Secretariat of Civil Aviation to keep him out of the country. Immigration spokesman Keo Vannthan told RFA he received the cabinet letter on Oct. 18. The letter ordered airline companies operating flights to Cambodia to stop Sam Rainsy from boarding planes to Cambodia and to report to authorities in the event he purchases a ticket to Cambodia. Any plane carrying Sam Rainsy would be turned back without being allowed to land in the country, said the letter. Although there was no new arrest order, immigration police are required prevent him from entering the country, it said. Sam Rainsy, however, told RFA in a call-in radio show on Friday that he will "definitely return to Cambodia during the 2017 election campaign" regardless of whether his request for a royal pardon is granted or rejected. "I am not surprises about the government's order. But the letter shows that I am not guilty, that I did nothing wrong, since it only bans me from entering Cambodia, but does not call for my arrest,"he said. "I do not want to cause trouble to passengers aboard the plane with me. It is not necessary for me to enter Cambodia via plane. I can enter Cambodia by sea or by land." Sam Rainsy cited the precedent in 2013, when King Sihamoni granted him a royal pardon. At the time Hun Sen had signed off on the Royal Pardon, which absolved Sam Rainsy of defamation charges, allowing him to return to Cambodia without being put in jail. Even though he was ineligible for candidacy in the 2013 general election, thousands of his supporters thronged the streets when he returned. In November 2015, Sam Rainsy was removed from parliament by the Hun Sen's ruling Cambodian People's Party, when a warrant was issued for his arrest after being convicted of defaming former Foreign Minister Hor Namhong with the claim that the CPP politician ran a prison in the 1970s for the bloody Khmer Rouge regime.