"From January 14, people will not get permits to build houses in Kathmandu unless they allocate space in their house maps to plant at least two trees," said Kedar Bahadur Adhiari, the CEO of the Kathmandu Metropolitan City Office.
"People who want to build houses in very small plots of land will be required to keep potted plants atop their house roofs," Adhikari told Japanese news agency 'Kyodo News'.
"We will strictly monitor whether the provision is adhered to," he said.
With more than 1.5 million people, the Kathmandu Valley, which includes the cities of Lalitpur, Bhaktapur, Kirtipur and Thimithe, is the most important urban concentration in Nepal.
Sprawling urban population has led to the lush valley losing much of its forest cover, which has reportedly decreased from 33 per cent in 1999 to around 10 per cent at present.
"Kathmandu Metropolitan City officials are forging separate greenery policies for houses already built and for apartments that have mushroomed in the capital in the past decade," Adhikari said.