"Our cities have to become more liveable and more people-friendly. All this can be possible only with rapid public transport," Singh said at a metro stop in Connaught Place in the capital's centre.
"In the absence of good reliable and affordable public transportation, private vehicles will dominate the roads, leading to congestion, pollution, more accidents and, of course, more fuel consumption. We can't force people to become dependent on costly private transportation." Singh took a return trip on the 22.8-kilometre (14-mile) route Friday morning ahead of its official opening to the public set for New Year's Eve.
Road traffic into the heart of Connaught Place was banned for three hours early Friday with security high in the wake of Wednesday's attack by a gunman on a science conference in India's southern technology hub Bangalore.
Initially 18 trains will run along the 22-station line from the suburban Dwarka residential area to the commercial centre of the city.