New Delhi, Dec. 2 -- India's telecoms ministry has directed smartphone manufacturers to pre-install a government-run cybersecurity app on all new devices, according to a government order, raising concerns of data privacy and user consent in one of the largest handset markets in the world.

The Ministry of Communications' order issued Monday asked smartphone makers to pre-install the government's "Sanchar Saathi" app on all new devices within 90 days and to prevent users from deleting it. The order also requires manufacturers to push the app onto older models through a software update, extending the mandate beyond phones available in the market.

The ministry said the app, which is available to India's 1.2 billion smartphone users, was ess...