The Hong Kong government has shelved highly anticipated talks with student leaders after the latter pledged to continue or even escalate disruptions to the public.

The students said they will carry out their threat unless the talks lead to substantial progress being made on their demands for how the city's leader should be elected in 2017.

Hong Kong's Chief Secretary Carrie Lam said on Thursday that the high-level task force in charge of electoral reform, which had become disappointed and frustrated by the students' recent remarks, decided that the basis for constructive talks has been undermined.

Lam reaffirmed the government's sincerity to engage in dialogue with the students, but said that in order to take matters forward, both sides must observe the "constitutional basis" (the Basic Law) and relevant decisions adopted by the National People's Congress Standing Committee.

On Oct 2, city authorities agreed to talk to the Hong Kong Federation of Students, as the federation's invitation letter did not specify goals for the discussions. But Lam said the Hong Kong government was disappointed to learn on Thursday that student leaders were insisting that the top legislature's decision covering election of the next chief executive be overturned.

Lam said student leaders vowed to continue with their protests. Their allies also threatened to stage more class boycotts among secondary school students, while opposition lawmakers plan to block funding requests in the legislature.

Lam also said the outcome of the protests must not hinge on talks, and the authorities will not accept use of the public's well-being as a bargaining chip. Officials are also worried that the talks might be used as an excuse to incite more people to join the protests, she said.

The chief secretary did not rule out clearing the blockades by force, as law enforcers have been given full authority to uphold law and order. She urged the protesters to use "wisdom and pragmatism" and spare "time and patience", to build consensus among all stakeholders.