Vehicles weighing more than 350kg, along with forklifts, trucks, cranes and trailers, are barred from most roads in Malé and Hulhumalé during two periods each day under rules that took effect on Wednesday.
The restricted hours are 6:00am to 8:30am and 11:30am to 1:30pm, the Economic and Transport Ministry said in an announcement.
During those hours such vehicles may use only Boduthakurufaanu Magu. They are barred from all other roads in Malé, from the roads of Hulhumalé, and from the Sinamalé Bridge and the highway linking the two.
The ministry said the measure is intended to make roads in the Malé area easier and safer for pedestrians and drivers alike. The restricted hours cover the times schools and offices generally open, and the middle of the day when schools finish.
Drivers who breach the restriction can face action under the Land Transport Act, the announcement said.
Transport Minister Mohamed Saeed said on Tuesday that the ministry had been discussing the timings with businesses for about four months, and was working towards a solution that would suit most people.
Heavy vehicles moving through congested streets at school opening and closing times have drawn mounting public complaints, and have been involved in serious accidents in the past.
Similar restrictions have been placed on Malé's roads before and were later relaxed.