Road Transport Department enforcement director Salim Parlan said the cars would not be allowed in if they failed a test at the border.

'Only vehicles with at least 70 per cent level of light penetration in the front windscreen and 50 per cent on the rear windscreen and side windows will be allowed,' he said, but did not indicate when the new law will take effect.

There was a controversy in April after several Singapore cars with dark tinted windows were given tickets in Malaysia. The problem boils down to different rules in the two countries on tint levels.

Singapore's Land Transport Authority requires 70 per cent of light to be let in through the windscreen and side windows in front, and 25 per cent of the light for the rear windscreen and windows.

The Star/Asia News Network