People in New Delhi have been warned to prepare for a potential major earthquake after the Indian capital was wobbled by a rare series of tremors in recent months.

Experts said a major quake is unlikely but not impossible and could kill hundreds of thousands in the crowded megacity of 20 million.

An awareness campaign launched on Thursday included double-page adverts in national newspapers with a list of dos and don'ts in an earthquake.

"Since April 2020, 18 very mild tremors have taken place in and around Delhi. Only two of these have registered above 4, or mild intensity, on the Richter scale," the city's chief minister Arvind Kejriwal said.

"However, as your chief minister, it is my firm belief that Delhi must always be prepared and aware of any crisis," he said in a statement.

Scientist J.L. Gautam from the National Centre for Seismology said a rise in the frequency of tremors was not unheard of in Delhi, but the city government was right to be spreading awareness.

"It's not a linear phenomenon -- sometimes there is a higher number of earthquakes and at times they are fewer. What the Delhi government is doing in planning is definitely a good thing," he told AFP.

Gautam said if the city were to be hit by a high-magnitude quake, hundreds of thousands of residents could lose their lives because many buildings were poorly constructed.

AFP