The victory of Cambodia's ruling party, led by Prime Minister Hun Sen, will help stabilize the situation in the country, observers said on Monday.

However, he is facing mounting pressure to bring about social reform, they added.

Late on Sunday, the ruling Cambodian People's Party announced it had won "an absolute majority of seats" in the general election, but the main opposition Cambodia National Rescue Party rejected the results, alleging widespread irregularities.

Official results from the National Election Committee are still unavailable.

If Hun Sen is formally reappointed, most of the government's existing policies will be continued, said Song Yinghui, a researcher on Southeast Asian studies with the China Institutes of Contemporary International Relations.

Despite its claim of absolute victory, Hun Sen's party saw a remarkable decline in the numbers of seats it secured.

Preliminary results showed the CPP won 68 seats and the main opposition CNRP took the remaining 55 seats in Sunday's poll, Khieu Kanharith, spokesman for the present Cambodian government and the CPP was quoted as saying by Xinhua News Agency on Sunday.

In the last elections in 2008, the CPP won 90 of the 123 seats in parliament while the leading opposition party took 29.

Xu Liping, a researcher of Southeast Asian studies with the Chinese Academy of Social Sciences, said it is highly likely Hun Sen will be reappointed and build a coalition.

The CPP will no longer dominate the government, Xu said, but Hun Sen is a mature politician and able to handle the complicated situation smoothly.

Meanwhile, a group of international observers said on Monday that Cambodia's general election on Sunday was fair, despite the kingdom's main opposition party rejecting the results.

"The election was free, fair and transparent, and, above all, peaceful, non-violent and smooth," Jose de Venecia, former speaker of the Philippines, who led a group of international observers from the International Conference of Asian Political Parties and the Centrist Asia Pacific Democrats International, said at a news conference.

"This bears testimony to the fact that Cambodian democracy has not only matured, but come of age politically," he said.

The observers visited more than a dozen polling stations, some pre-arranged visits and some random, within Phnom Penh and provinces on its outskirts.

Sam Rainsy, the CNRP leader who just returned from a four-year overseas exile, told reporters at a news conference on Monday, "The party calls for the establishment of a joint committee in order to investigate the irregularities such as vote counting and duplicated names of voters."

The CNRP said the committee should report back by Aug 31.

Kem Sokha, the CNRP's vice-president, said the party did not recognize the election results, but would not abandon the seats it won in the election.

Hun Sen's CPP is a symbol of conservative political forces in Cambodia, supported by a relatively older generation, while the CNRP is mostly the party of the youth, who are influenced by Western culture and values.

"No matter which party wins the election eventually, Cambodia will implement a China-friendly policy", Song said. Addressing issues such as corruption and the gap between the country's rich and poor required more effort from the new government, no matter if it is led by a single party or a coalition, she added.

Xinhua contributed to this story.

zhouwa@chinadaily.com.cn