Bus companies have started testing a huge four-axle bus in the hope authorities will allow the monster vehicle on to the roads.
The double-decker, built by German manufacturer Neoplan, exceeds the maximum legal length of 12 metres by three metres, making it the largest non-articulated bus in the world.
KMB and Citybus want to introduce the vehicle, which they say is necessary for busy, long-haul routes such as cross-border, airport and new town to urban area trips.
In the hope of changing the rules to allow the bus on the roads, the companies have invited Transport Department engineers and police to inspect a left-hand-drive model being tested in coming weeks.
KMB engineering manager John Brownhill said the bus's all-wheel steering mechanism gave it the same turning circle as existing 12-metre three-axle buses.
Mr Brownhill said the bus could carry 200 passengers, or a third more people than buses now on the roads.