An independent China strategist says Hong Kong's sole Chief Executive candidate, John Lee, will need to appoint capable ministers in order to secure achievements in his first 100 days in office.

Speaking on RTHK's Hong Kong Today programme on Tuesday, Andrew Leung said the "results-oriented" approach set out by Lee is "spot on", but questioned how the former chief secretary would achieve it.

In his manifesto, released on Friday, Lee said he would use key performance indicators (KPIs) to monitor results.

Leung welcomed that approach, but said the incoming CE would face challenges in overcoming what he called a "silo" or rigid mentality in the civil service.

"The delivery of all these things in the hundred days depends on a choice of very, very good, capable ministers," Leung told RTHK's Janice Wong.

"And the ministers should be carefully chosen based on their sheer abilities rather than, kind of, as a reward for past loyalty or anything like that."

Leung also said Beijing valued Lee's background as security minister and, before that, as a senior police officer.

"I think Beijing has woken up to the fact that both mainland China and Hong Kong are facing challenges not seen in 100 years as China's now entering the deep waters domestically and grappling with a number of issues externally," Leung said.

"The United States is putting unprecedented pressure on China and using a lot of cards, including Hong Kong, to undermine China's trajectory. And so China needs someone who's stern, who's strong, and has a security background."

The Chief Executive election takes place on Sunday.