At least two number plate manufacturers have been importing the moulds for these plates directly from Europe, fonts and all, at the cost of up to $80,000.

But the EU number plates use letter and number fonts that are smaller than the Land Transport Authority requires them to be, and their colours might be against the rules, too.

For instance, letters and numbers on licence plates on Singapore registered cars must be 70 mm high and 50 mm wide.

But those on many of the EU-inspired plates here are 10mm narrower, confirmed Mr Winson Ng, a branch supervisor for MRS Sign, one of the biggest manufacturers of such plates.

That difference might make them harder to read when, for example, there is a hit-and-run accident, and may be harder to pick up on, for example, by carpark surveillance cameras should there be an incident.

It is among several reasons why they are not allowed.

Read the full report in Friday's edition of The Straits Times.