Commuters travelling on an extended section of the BTS elevated Green Line linking Soi Bearing and Samrong, will get free trips until the end of this year.
The fare exemption for the one-station extension was earlier set to last until April 30, but Prime Minister Prayut Chan-o-cha said he asked the operator to extend the free service until the end of this year.
The first station of the Green Line's second eastern extension was officially opened on Monday in a ceremony presided over by Gen Prayut. Construction of the station was completed late last year.
While visiting the station and testing the system from Samrong to Bearing station, Gen Prayut told the crowd attending the ceremony that "the free service will be offered for all of 2017". But the Bangkok Metropolitan Administration (BMA), owner of the project, said the free ride would be for April only.
Bangkok governor Aswin Kwanmuang said Krungthep Thanakom Co, a company owned by BMA, had installed the operating system for the section. City Hall has tested the service since March 15 but the service was opened to the public from 1pm Monday.
The official opening of the Samrong station on Monday marked the connection between the first and the second eastern extensions of the Green Line. The completed 5.25km first extension runs from On Nut to Bearing while the 13km second extension is from Samrong to Samut Prakan.
After the Samrong station, the remaining eight stations of the second extension will be opened by 2018: Pu Chao, Chang Erawan, Royal Thai Naval Academy, Pak Nam, Srinagarindra, Phraek Sa, Sai Luat and Kheha.
A 1,200-car parking building will also be constructed at the end of the route.