Under the provisions of the directive, the government will declare a list of trusted sources and trusted products for installation in the country's telecom network.
The Supreme Court cautioned the telecom firms and said that failure to pay installments of AGR-related dues would incur penalty, interest and contempt of court.
The decline in subscriber base during April was preceded by a loss of 28 lakh connections in March, which saw the lockdown being imposed towards the end, India Ratings and Research said.
Official sources said that the government had told BSNL not to use Chinese equipment in 4G upgrade, and that implementation of the direction meant that the company had to issue a new tender.
Mobile data charges in India are by far the cheapest in the world even as the demand for mobile data services continue to grow rapidly, the company said.