Chief Executive Leung Chun-ying said meeting radical lawmakers' demands in exchange for an end to their filibustering of the budget bill was "extremely inadvisable".
Leung also echoed earlier warnings the city could fall off "a financial cliff" if the bill failed to be passed by next week.
Leung's remarks came a day before a meeting among lawmakers from People Power and the League of Social Democrats and Financial Secretary John Tsang Chun-wah. Tsang hopes to convince the four lawmakers to withdraw more than 700 amendments they filed to the annual appropriation bill.
In the Legislative Council's question and answer session yesterday, Leung issued what was perhaps his sternest warning yet over the filibustering attempt.
"Hong Kong has never been in such a crisis, so many people are not aware of the severity of the situation," Leung said. "A failure to pass the bill in time will lead to huge damage to the city's global reputation."
He agreed with the description that "a financial cliff" loomed - the term used by unionist lawmaker Wong Kwok-hing.
Leung said the financial secretary had already indicated he would communicate with all lawmakers to solve the problem, but added: "It will be extremely inadvisable if the government has to make deals with the lawmakers in exchange for an end to the filibuster."
The four radical lawmakers were expelled from the session after shouting slogans during Leung's opening speech. People Power's Albert Chan Wai-yip said Leung's criticisms over the filibuster disregarded lawmakers' duty to monitor the government.
Chan said they could stop the filibuster if the government met their demands of either a universal cash handout of HK$10,000 or a consultation on a universal pension scheme.
In a letter addressed to lawmakers yesterday, the financial chief said government departments were now assessing cash flows for the coming two months and drafting contingency plans in light of the progress of the debate.