A new trial speed limit of up to 120kph for private cars has been imposed on three highways, namely Asian, Pahonyothin and Mitraparb (Friendship), since Monday.

According to Transport Minister Saksayam Chidchob, the increased speed limit is on a trial basis on the Asian Highway, from Bang Pa-in in Ayutthaya to Nakhon Sawan, covering a distance of 150km, Mitraparb highway from Bangkok to Nakhon Ratchasima and Pahonyothin northbound from Bangkok.

The three highways are divided into three traffic lanes for different speeds, namely under 80kph, between 80-100kph and 101-120kph.

Mr. Saksayam said a recent opinion poll showed that 71% of motorists agreed with the raised limit, from 90 to 120kph, against the 29% who think road conditions in Thailand are not ready for increased limits and some motorists lack discipline and driving skills.

The survey also showed that 32% of motorists admitted they regularly exceed the 90kph limit.

To cope with the increased speed limit, the Highways Department and Local Highways Department have been instructed to install safety equipment, improve road barriers and lane markings and recalibrate equipment used to check the speed of vehicles.

The speed limit for public transport, such as buses and trucks, remains at 90kph.