Story highlights Xi arrived in Hong Kong on Thursday, he leaves on Saturday

He'll attend a ceremony to mark the 20-year handover anniversary

Hong Kong (CNN) China's President Xi Jinping underlined his commitment to "one country, two systems" as he arrived in Hong Kong to mark two decades of Chinese rule in the former British territory.

"For the past 20 years, Hong Kong has always had the strong backing of the central government," Xi said Thursday as he addressed crowds at the city's airport.

It's Xi's first visit as Chinese leader to the special administrative region. From the tarmac, he encouraged Hong Kongers to "look forward to the future, making sure 'one country, two systems' can work smoothly and continue," referring to the principle by which Hong Kong retains limited autonomy and freedoms.

Xi said the 20th anniversary of the city's handover from the United Kingdom to China on July 1 is a huge event "for the country, and for Hong Kong."

China's President Xi Jinping and his wife, Peng Liyuan, arrive in Hong Kong on June 29.

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