The door to the court was locked when Sam Rainsy arrived. After a security guard let him in, prosecutors did not show up to receive the documents he wanted to file in his defence, he said.
“The prosecutors all fled. They are scared by Sam Rainsy,” he told reporters as he left the court.
Foreign Minister Hor Namhong filed a defamation lawsuit in April at Phnom Penh Municipal Court against Sam Rainsy over remarks alleging that he was a former Khmer Rouge member.
Hor Namhong has long said that he and his family were prisoners at a Khmer Rouge camp, and has successfully sued people in the past for claiming that he had links to the regime.
Sam Rainsy, who leads the main opposition party running in general elections on July 27, went voluntarily to the court on Wednesday to submit documents in his defence.
He accused the court of being “vulgar and a puppet” and urged the people to “open a new page of history in this year’s election” to oust the government.
“The election is near and they want to intimidate me but I’m not scared,” Sam Rainsy added.
Court officials could not be reached for comments immediately.
Sam Rainsy and his eponymous party are considered the main opposition force when Cambodians go to the polls, but Prime Minister Hun Sen’s ruling Cambodian People’s Party (CPP) is expected to dominate the election.
Up to two million people died of overwork and starvation or were executed under the Khmer Rouge, which outlawed religion, property rights, currency and schools during its 1975-1979 rule.