Vice-President Li Yuanchao called on youth in Hong Kong to safeguard the rule of law and support the Hong Kong government to proceed with electoral reform in accordance with the Basic Law.

His call comes after a controversial poll and amid celebrations and protests on the anniversary of Hong Kong's return to China.

Li told about 2,000 Hong Kong youths at the Great Hall of the People in Beijing on Tuesday that the Basic Law is the most important constitutional guarantee of the "one country, two systems" policy and Hong Kong's stability and prosperity.

Li said he hopes Hong Kong youth can reinforce their awareness of the rule of law in order to safeguard the city's stability and support the local government reform of the 2017 chief executive election within the framework of the Basic Law and relevant decisions by the National People's Congress Standing Committee in a gradual and orderly manner.

On Tuesday, the Hong Kong government and residents held more than 200 activities to mark the return of the special administrative region to China 17 years ago, including flag-raisings and visits to the garrison of the Chinese army. Organizers estimated that 450,000 attended these activities.

At the same time, two youth associations in Hong Kong staged overnight rallies in Central on Tuesday night demanding the central and special administrative region governments accept their demands in relation to the ongoing political reform in Hong Kong. Tens of thousands of people joined the rally, according to the Associated Press.

Speaking after the handover celebration activities on Tuesday, Zhang Xiaoming, director of the central government's liaison office in the city, said the central government is behind Hong Kong in its progress to universal suffrage in the chief executive election in 2017.

"I hope the future of universal suffrage in Hong Kong is like the weather today in that after the wind and rain, we can still see the rainbow," he said.

Zhang added that such determination will not be changed or shaken by the scale of the so-called "referendum" voting or the march.

He said people's legal rights and liberties, including the freedom of assembly and procession, are fully respected. After the handover, such liberties have not decreased but in fact increased.

He believed the mainstream opinion is to maintain stable and harmonious development and every eligible voter is able to choose the chief executive in 2017.

However, he is against the radical, unlawful activities of some groups and said everyone has a duty to respect the rule of law.

Hong Kong Chief Executive Leung Chun-ying said Hong Kong's achievements in the past 17 years have not come easily and called on all citizens to cherish such accomplishments.

As for constitutional development, he stressed that it must conform to the Basic Law and decisions of the National People's Congress Standing Committee.

Leung went on to say that constitutional development is a major task of the current government.

"The SAR government and I will demonstrate the greatest determination and sincerity to forge consensus in society to fulfill the goal with a view to implementing the chief executive election by universal suffrage in 2017," he said.