Indian capital world's most populous city: UN report

The Indian capital has been ranked as the world's most populous city by the United Nations.

According to a report by the United Nations, Delhi's population has doubled to 25 million since 1990, making it the most populous city of the world, after Tokyo.

Mumbai also made it to the top 10, securing the fourth place in the list of the world's most populous cities with some 21 million population.

Shanghai came on the third spot with 23 million population, according to the report.