SINGAPORE - Downtown Line 2 (DTL2) was described by Prime Minister Lee Hsien Loong as a key step in Singapore's journey towards becoming a car-lite city.

Already, two million people take the bus or train at least twice a day to get to the office or school and then back home again. "Public transport is the most efficient way for our people to get around in a compact city like ours... Ultimately we aim to make Singapore a safe, green, car-lite city," said Mr Lee, as he opened the new line on Saturday.

The 12-station DTL2 begins operation on Sunday. It starts in Bukit Panjang and passes through the Bukit Timah corridor towards Rochor before connecting to Downtown Line 1 at Bugis station. Commuters who start and end their journeys on the line will enjoy six days of free travel from Sunday.

"In the last decade, we have been investing heavily to make public transport accessible, comprehensive and convenient so that it becomes your transport mode of choice," said PM Lee at the opening ceremony held at Botanical Gardens Downtown Line station.

A new MRT line and extension will be opened almost annually from next year onwards, doubling the rail network to 360km by 2030. Such a network will be comparable to those in London, New York and Tokyo. For commuters, the expansion will mean that eight in 10 homes will be within a 10-minute walk of a train station.

The Downtown Line was first mooted as the Bukit Timah Line in 2001 by former Transport Minister Yeo Cheow Tong. After further study, it evolved into the longer Downtown Line which would link Bukit Timah to the city and the east.

Close to 30 schools are within a 10-minute walk to stations along DTL2's route. With the new line, PM Lee hope morning jams along Bukit Timah Road will become a thing of the past.