Hong Kong's top politician Carrie Lam said she is "very disappointed" by the Moody's ratings downgrade for the city-state.

Speaking to CNBC's Geoff Cutmore at the World Economic Forum (WEF) in Davos Lam said: "We are very disappointed by the downgrading by Moody's from Aa2 to Aa3."

The chief executive said she was even more upset by the reasons given by the ratings agency.

"If you ask me, I am even more disappointed by their assessment of the Hong Kong situation and their comment on the 'weak institutions and governance,' because after seven months of unrest, what has proven to be resilient is Hong Kong's institutions and governance."

Last week, Lam announced a $1.3 billion fiscal pledge, designed to kickstart Hong Kong's muddling economy back into life. On Tuesday, Moody's ratings agency appeared to dismiss that plan by cutting the city's rating by one level. Fellow ratings agency Fitch had already downgraded the city-state in September last year.