There has been a bottleneck of new car models at the Land Transport Authority (LTA), which inspects, evaluates and approves new models before they can go on sale in Singapore. The process, known as homologation, is taking longer in recent months.

The authority explained that it is "currently reviewing the Vehicle and Inspection Type Approval System process", and hence, more lead time is required to gather and evaluate information on the cars.

New vehicles such as the Porsche Panamera S E-Hybrid, the first of its kind in Singapore, is taking a whole lot longer to homologate. The plug-in petrol-electric car has arrived since last November, but has yet to be approved.

A plug-in hybrid version of the Mitsubishi Outlander has also been awaiting approval since January.

There have been sources saying that the LTA wants to make sure Category A cars imported do not produce more than 130bhp, and also to have assurance from the industry that engine output cannot be raised after they are sold.

There is also talk that the authority is looking at including Open Market Value (OMV) as an additional element in COE categorisation.

In view of the issue, President of the Motor Traders Association Mr. Glenn Tan said the trade body is currently compiling a list of cars affected by the delay, and will bring up the matter to the authority at the end of the month.