Updated

Cambodia's prime minister has lifted a ban on the return to the country of his main rival, daring him to risk imprisonment under an outstanding criminal conviction.

The order issued Wednesday by Hun Sen allowing the return of Sam Rainsy, for two decades his most persistent political opponent, comes as attention is being turned to next year's general election.

Hun Sen has repeatedly sought to sideline Sam Rainsy, especially by pursuing defamation cases against him. Sam Rainsy has stayed abroad since late 2015, when a conviction he believed was covered by a pardon was revived. Last October, he was officially banned from re-entering the country.

The new order forces Sam Rainsy to make good on a vow to return if the ban was lifted, or risk losing face.