Cosmetics giant Lancome closed some of its outlets in Hong Kong on Wednesday ahead of protests, after the company cancelled a concert featuring a local singer critical of China.

Many residents believe the promotional gig by pro-democracy activist Denise Ho was cancelled after China's state-run media criticised the French company for allowing her to perform.

Hong Kong's Ho was a leading activist during mass rallies in 2014 calling on Beijing to allow fully free elections.

The row comes as fears grow in the semi-autonomous city that Beijing is tightening its grip.

Lancome's counter at the major Times Square shopping mall in central Hong Kong was closed Wednesday, as was its beauty centre in the same building, ahead of a planned afternoon protest nearby.

Organisers warned of more action if it does not respond to swelling public anger.

"The key point of this protest is to show the world that we should unite together and, through boycotting (their products), show Lancome and L'Oreal that you cannot just focus on the China market," said Avery Ng, chairmain of the League of Social Democrats, one of a dozen groups planning to join the protest.

Parent company L'Oreal's Hong Kong headquarters in Times Square was also shut. Local media reported the company had issued an internal memo Tuesday asking staff to take the day off.

A petition on the website change.org asking people to boycott Lancome products has gathered more than 4,000 signatures.

"The civilised world needs to stop kowtowing to China. Make an example of Lancome for disrespecting the people of Hong Kong and freedom," Lawrence Lau from Hong Kong, commented on the petition site.

Politicians have also voiced anger.

District councillor Christine Fong flushed her Lancome products down the toilet in a video posted on Facebook, watched more than 128,000 times by Wednesday morning.

"I'm going to squeeze out all of this brand's product and I will never use them again. Lancome go to hell!" she said, as she squeezed a tube of cream down the toilet.

The row kicked of Saturday when China's Global Times accused Lancome of cooperating with a "Hong Kong poison" and a "Tibet poison" -- a reference to Ho's praise for the Dalai Lama.

The concert was also slammed on mainland social media with critics saying Lancome was using money from Chinese customers to support independence for Hong Kong and Tibet.

Lancome announced the cancellation of the concert Sunday, citing "possible safety reasons".

Ho herself has hit back, saying: "This is not only about me. This is about those who believe in freedom, justice and equality."

Hong Kong returned to China in 1997 under a "One country, two systems" agreement and enjoys much greater liberties than in mainland China, but there are fears they are being eroded.