Prime Minister Prayut Chan-o-cha has issued a promise to build more mass-transit systems for commuters in the capital, following the success of the new Blue Line extension, which on Monday launched full-scale services from the suburb of Lak Song to Hua Lamphong station.
A two-month trial run saw up to 2.5 million people use the new service, according to the Mass Rapid Transit Authority of Thailand (MRTA), the developer.
"The government wants to gear up and modernise transport systems for all people. We have to fill all major areas with these electric trains," Gen Prayut said, as he rode the Blue Line from the outer Tha Phra district to Wat Mangkon next to Chinatown.
The premier said the Blue Line and other electric rail routes scheduled for completion in the next couple of years would help curb air pollution and also tackle climate change caused by polluting road vehicles.
As high levels of fine PM 2.5 dust returned on Monday, Bangkok's air was rated the worst in the world, according to crowd-sourced data at the monitoring site IQAir AirVisual.
Second and third on the list were Vietnam's capital Hanoi and China's Chengdu.
Gen Prayut also referred to Bangkok's notorious traffic congestion.
"Traffic problems can be relieved if Bangkok residents, particularly motorists, have more choices to travel, and a rail network should be one of them," he said.
To improve the service and attract more commuters, Blue Line trains at the outlying Lak Song will begin operating at 5.40am rather than 6am.
The Lak Song-Hua Lamphong section, which connects with the Blue Line's 23km subway tract running further to Tao Poon, will serve people until midnight.
Passengers can save 33% on the price if they buy special tickets for more than 15 journeys, Mr Pakapong said.
He expects daily passenger numbers to increase to 800,000 when the other Blue Line extension, running from Tha Phra-Bang Sue, opens in March next year.