The government has ordered the removal of all mesh netting on buildings undergoing major renovation across Hong Kong by Saturday, citing public safety and people's concerns in the wake of the deadly Wang Fuk Court fire.

Speaking to reporters in a briefing, Development Secretary Bernadette Linn said the protective netting of more than 200 private buildings, along with more than 10 public housing and government premises, will have to be removed, and that contractors have to bear the costs.

The minister said officials will look to issue a new set of rules by next week, allowing only netting that passed safety tests to be installed.

Linn said this doesn't mean that existing netting has issues, but stressed that anyone found to have put up substandard netting would be punished.

She said officials from various departments have taken samples from more than 300 buildings in recent days.

"For example, Buildings Department officers took samples from each of the private building in a stringent manner. Staff collected thousands of bamboo scaffolding samples from the lower, middle and higher floors, including the very high floors," Linn said.

"They're gradually taken to designated laboratories for tests, and if we find any non-compliance, we'll pursue the matter until the very end."

The development chief said if contractors have problems taking down the netting, they need to inform officials for them to determine if the reasons given are valid.

The government said earlier this week that seven of the mesh-netting samples taken from Wang Fuk Court were found not to be flame-retardant.

Meanwhile, authorities said at least two renovation projects are suspected to have used forged documents claiming that the netting passed mainland safety tests.

Security minister Chris Tang said anti-crime officers were investigating two projects, involving Fung Wah Estate in Chai Wan and Fortress Garden in Fortress Hill.

He said certification of the netting used pointed to the materials having passed tests on the mainland, but officers found that mainland authorities either didn't issue the test reports or that the phone numbers provided don't exist.