Legislators are being lobbied to reject a bill allowing lawmakers to vet rises in bus fares.
Democratic Party legislator Lau Chin-shek plans to put his private member's bill to the vote on June 26.
His move will force the bills committee scrutinising the bill to dissolve - even though committee members from other political factions have said they need more time to look at the proposal.
In a letter dated June 11, Secretary for Transport Haider Barma said: 'The bill, if enacted, will undermine business confidence and discourage private sector investment in public transport services and projects in transport infrastructure.' Mr Barma said bus companies had entered into their franchises on the understanding that bus fare revisions were determined by the Governor in Council alone, and the bill, if enacted, would represent a major deviation from this understanding.
He said the Government already had a well-established bus fare revision mechanism to ensure the approved rate of increase was justified.
But Mr Lau said there was not enough supervision of bus companies.