Deputy government spokeswoman Traisuree Taisaranakul said the cabinet approved in principle a draft regulation on speed limits on highways as proposed by the Transport Ministry.
The regulation is applicable to highways with at least two lanes running in the same direction and traffic islands with barriers. The roads also must not have a ground-level U-turn slot.
The new speed limits are expected to improve traffic flow, she said.
The speed limit for trucks weighing over 2,200kg and buses with more than 15 passengers is 90km/h, while buses with 7-15 passengers are allowed to go up to 100km/h.
Smaller motorcycles won’t be allowed to exceed 80km/h, while those with 400cc engines and 35-kilowatt engines and above are limited to 100km/h.
School buses must not exceed a speed limit of 80km/h.
The speed limit for vehicles travelling in the furthest right lane is no less than 100km/h.