As a planned shake-up of the electoral system is poised to rewrite Hong Kong's political landscape, young people can be trusted with the city's future as they forge new careers in politics, Hong Kong Chief Secretary for Administration Matthew Cheung Kin-chung said.

The city will see a "new vista and landscape" in its legislature, with patriots working with "one heart, one mind and one purpose", once the electoral mechanism is improved, he said.

"There is a new unity of purpose and mission being the cement to bind everybody together," Cheung said. "It's really about Hong Kong's future and the steady implementation of the 'one country, two systems' principle."

"More young patriots will be encouraged to come out in the future and regard politics as a natural choice of a career. I would say the time is ripe to start thinking about it," Cheung said.

Under the overarching principle of "patriots governing Hong Kong", the criteria for young candidates seeking public office are clear, Cheung said. As is the case in every country, he said they must be law-abiding citizens, with a love for the motherland and commitment to protecting the nation's sovereignty and interests.

"These are the basic, minimum requirements, which are also absolutely reasonable," Cheung said.

Cheung, who began his public career as an information officer in 1972 and took up his post as chief secretary in 2017, stands as an experienced practitioner of those virtues.

Cheung recalled how his patriotism and a strong sense of mission inspired him to fight against misconceptions about the Chinese mainland and Hong Kong, when he attended meetings of the United Nations Human Rights Council in Geneva in November 2018 and March 2019.

As deputy head of the China delegation, Cheung said every word in his powerful speeches was uttered from the heart, with great respect and admiration for the remarkable achievements China had made over the past seven decades.

"I held my head up high when I walked into the meeting hall, feeling quite proud to represent our county," he said. "This is just one of many moments when I truly felt patriotism is an essential virtue for people holding public office, especially at such solid events overseas."

While responsibilities and missions inspire Cheung, difficulties and challenges also test him.

Amid the protracted Sino-US trade skirmishes, festering violent protests and the coronavirus pandemic, Cheung described the past two roller-coaster years as an "unprecedented challenge", forcing the special administrative region government into unchartered territory.

As Cheung looked back on that time as "a rewarding experience", the most unforgettable policy challenge during his public career came 10 years ago when he fought a lone battle to implement a statutory minimum wage.

"The second session of the final LegCo debate lasted 20 hours, nonstop," recalled Cheung, who at the time was secretary for labour and welfare. "Without undersecretaries, I fought it alone."

Cheung got the bill passed in the end, which he deemed "a victory for Hong Kong's lowest-paid workers who had been striving for years without any success". In May 2011, the minimum wage came into force at HK$28 (US$3.60) per hour. The current rate is HK$37.5 per hour.

"A career in politics should be a mission," Cheung said, highlighting the attributes and beliefs that young patriots in public office should epitomize.

"As an official, you should have a heart for the underprivileged and the local community," he said. "Make sure the SAR government, in a more cooperative, constructive and harmonious environment, is more responsive to the concerns of ordinary people and can propel Hong Kong forward."