Police pledged on Friday to deploy sufficient manpower to manage the hundreds of thousands of revellers expected to flock to both sides of Victoria Harbour for the National Day fireworks.

Ho Chun-hin, the acting superintendent for Kowloon West traffic, said crowds watching the 23-minute display on October 1 could reach last year's levels.

"According to our past experience... the number of people on both sides of the harbour had reached 290,000 during peak hours at the last National Day fireworks display," he said.

"We expect we will have to handle a similar size crowd this time as well," he said.

"I can assure [people] that the police will have sufficient manpower and will adopt the most appropriate crowd management measures to ensure the public can enjoy the event in a safe and orderly manner."

But Ho did not reveal the number of officers to be deployed.

Parts of the city near popular viewing spots on both sides of the harbour will be closed off.

The area around Golden Bauhinia Square will be closed at 4pm, while road closures for certain parts of Hong Kong Island will begin from 6.30pm.

On the Kowloon side, road closures will start from 5pm in Tsim Sha Tsui and West Kowloon Cultural District.

To facilitate cross-border travel, there will be a temporary bus stop next to the West Kowloon terminus of the high speed rail to make it easier for visitors to get to Huanggang and Shenzhen Bay.