The revolt "aims mainly to divide (the country) and hit its geopolitical place and historic role in the region," he was quoted by state-run state agency SANA as saying.
Zhai, speaking to reporters following the meeting, said he was hopeful Syrian authorities would restore stability to the country soon.
He backed a referendum that is at the center of the regime's plan to defuse the unrest, and said China was "extremely concerned" about the escalation of the crisis. The referendum would decide on the country's new draft constitution that would create a multiparty system in Syria, ruled by the Assad family for 40 years.
The U.N. General Assembly voted overwhelmingly Thursday in favor of a nonbinding resolution backing an Arab League plan calling for Assad to step down and strongly condemning human rights violations by his regime. Russia and China vetoed a similar resolution in the Security Council and voted against the measure in the General Assembly.
"China has no selfish interests," Zhai said, defending the veto. He added that China's "objective and just" position on Syria stemmed from its basic interest in the welfare of the Syrian people.
China says the resolution put undue emphasis on pressuring the Syrian government and prejudged the result of any dialogue between the parties to the conflict.
The veto also appears to be rooted in China's deep-seated opposition to humanitarian intervention in other nations. China fears such intervention would legitimize outside interference in its own problems in the restive western regions of Xinjiang and Tibet.
Zhai urged Syrians to participate in the planned referendum
Assad's call for a referendum, set for Feb. 26, has raised the question of how a nationwide vote could be held at a time when many areas see daily battles between Syrian troops and rebel soldiers. The opposition has opposed the referendum.
Zhai said the referendum "would be in the interest of the Syrian people."
Only in light of stability could Syria conduct comprehensive political reforms, he said.
Associated Press reporter Albert Aji in Damascus, Syria, contributed to this report.