On December 18, the Ministry of Defence of Ukraine posted a video on Twitter to express gratitude to people from 52 countries and regions worldwide who "have fought alongside Ukraine", including Hong Kong.

However, the city was represented in the video by a regional flag of bauhinia in black colour, which was designed during the 2019 protest and broadly used by activists.

In a press conference this morning, Lee said the blunder was a diplomatic issue and will be dealt with through diplomatic methods.

The SAR government had communicated with China's Office of the Commissioner of the Ministry of Foreign Affairs in Hong Kong for further steps, he said.

Lee also said the government will talk to Alphabet Inc.'s Google about its search results for the city's national anthem, saying it was a "serious matter."

"We all know very well that Google has the means to do it; it's a question of whether Google chooses to do it. If it chooses not to do it, then I think it has a lot to explain," he added.

Lee stated that Google is a responsible company and hopes that they can work together for a solution to ensure that the right content is provided to the public, and to remove content that misrepresents and misleads.

A search for the city's anthem brings up articles and videos about Glory to Hong Kong, the unofficial song of the mass protests that rocked the financial hub in 2019, ahead of China's March of the Volunteers.

Hong Kong passed a law in June 2020 that imposed a prison sentence of up to three years for people convicted of insulting or denigrating the anthem.