When the opposition Cambodia National Rescue Party’s 55 lawmakers take their seats in parliament for the first time since last year’s disputed election, old foes will come face-to-face once more.

In the case of former prime minister Pen Sovann, now a CNRP lawmaker for Kampong Speu province, a bitter rivalry with Prime Minister Hun Sen will once again be confronted.

“I am excited . . . What I lost, I will have it again,” he said.

Sovann was prime minister of the Hanoi-backed People's Republic of Kampuchea from June to December 1981, before he was arrested and jailed in 1981 after floating the idea that Cambodia create a military independent from Vietnam. He also served as secretary-general of Kampuchean People's Revolutionary Party, a forerunner of the current ruling Cambodian People's Party, before his arrest.

He spent more than 10 years in a Vietnamese prison for falling afoul of Le Duc Tho, then Vietnam's chief adviser to the Kampuchean United Front for National Salvation, which Sovann helped found in 1978.

He was replaced by current National Assembly President Heng Samrin.

“Those who arrested me and sent me to jail, I will meet them again. But I will not seek to take revenge,” he said.

Returning to public life after nearly three decades in the shadows, the 78-year-old political veteran says he is looking forward to sparring with former colleagues in the CPP.

“When I rejoin the National Assembly, those [former colleagues] will know about me. I know that they will give me respect. Before, they misunderstood my ideas and they arrested me,” he said. “I expect that my former colleagues will see me and shake hands with me and strike up a conversation.”

Since his release from prison in 1992, Sovann's political career failed to take off until now. In 1998, he formed the National Support Party, before briefly allying with current CNRP president Sam Rainsy.

The party failed to win popular support and, in 2007, the former bodyguard to senior Khmer Rouge leader Ta Mok joined the Human Rights Party headed by CNRP deputy president Kem Sokha.

He stuck with the HRP until it joined with the Sam Rainsy Party in 2012 to form the CNRP, going on to win an unprecedented 55 seats in last year’s election.

“I have struggled for the Cambodian nation. My goals are still the same,” he said. "I am happy to meet with former colleagues, but I don't believe Cambodia should be subordinate to foreign powers as they do.”