Luxury fashion brands Versace and Coach have apologised for making perceived affronts to China's national sovereignty on t-shirts, mistakes that cost them their high-profile Chinese brand ambassadors.

Versace was criticised yesterday for a t-shirt that implied Hong Kong and Macau - both semi-autonomous cities in China - were independent.

Hong Kong, operated under China's "one country, two systems" policy, has become particularly sensitive in the mainland as the Asian financial hub has been plunged into months of pro-democracy protests.

Images of a 2018 Coach t-shirt that said Taiwan, a self-ruled democratic island, and Hong Kong were not part of China again provoked anger online.

Both companies have tried to minimise the damage.

Coach said in a statement that the clothes with the "serious inaccuracy" had been pulled, adding that they were "fully aware of the severity of this error and deeply regret it".

The brand corrected its website as well, after Chinese users shared screenshots online showing Hong Kong in a 'Find By Country' drop-down list.

Versace has also apologised. "We love China and resolutely respect China's territorial national sovereignty," the Italian brand wrote on its Weibo account.

The controversial t-shirts were removed from its official sales channels and "destroyed" on 24 July, the company explained.

The company's representative in China, actress Yang Mi, announced she would stop collaborating with Versace over the t-shirt incident, saying the brand was "suspected of damaging our country's national sovereignty".

Similarly, Coach's ambassador, Chinese model Liu Wen, announced she was terminating her work with the fashion brand over its t-shirt blunder.

"At all times, China's national sovereignty and territorial integrity are sacred and inviolable!" she posted on her official Twitter-like Weibo account.

"I love my motherland, and resolutely defend China's national sovereignty!" she wrote.

The two luxury brands are the latest examples of foreign companies that have run afoul of the many political sensitivities that go with operating in China's gigantic market.

Chinese authorities and state media have lashed out particularly in recent weeks at firms that appear to back the Hong Kong demonstrations, with flagship airline Cathay Pacific facing demands that staff who supported the protests are prevented from working on flights through Chinese airspace.

In May 2018, US clothing retailer Gap apologised over a t-shirt showing a map of mainland China that omitted Taiwan, a self-governing island that Beijing considers a rebel province awaiting reunification.

Italy's Dolce & Gabbana also apologised in November after its products were pulled from lucrative Chinese e-commerce platforms over an Instagram post seen in China as culturally offensive.