PHNOM PENH – The Cambodian opposition boycotted the opening of parliament Monday over alleged widespread cheating in July’s elections, putting the country’s political crisis at a critical juncture.

Empty seats dotted the National Assembly as 55 lawmakers elected from the opposition were absent, while 68 ruling party lawmakers attended the session.

Authoritarian Prime Minister Hun Sen was poised to continue his 28 years in power during a re-election vote scheduled for Tuesday’s session. He sat alongside other lawmakers during a swearing-in session and made no comment about the boycott.

The opposition Cambodia National Rescue Party says it was cheated out of a victory because of electoral fraud. It had vowed for weeks to boycott parliament unless the government agreed to an independent probe of the July 28 election results.

The government rejected the demand of an independent probe, and King Norodom Sihamoni had urged the opposition to take its seats at the assembly, pointing to a constitutional stipulation that the assembly must be convened within 60 days of the election.

“The Cambodian nation must stand united,” Sihamoni told the half-empty assembly as he convened parliament. He did not mention the boycott but called for an “active and vigorous implementation” of legal and judicial reforms — among the many reforms called for by the opposition.

As the ruling Cambodian People’s Party swore in its lawmakers, the opposition held its own symbolic ceremony far from the capital at the sacred temple of Angkor Wat, in Siem Reap.

The opposition lawmakers took an oath not to participate in government until justice is delivered, said Son Chhay, an opposition lawmaker. Talks last week between Hun Sen and opposition leader Sam Rainsy failed to break the deadlock.