New Delhi: The first phase of the Census and the exercise to update the National Population Register (NPR), scheduled for this year but deferred due to the coronavirus outbreak, may be delayed by a year as there is no sign of slowdown of the pandemic.

The Indian census is one of the largest administrative and statistical exercises in the world, with the involvement of more than 30 lakh officials who would visit each household across the length and breadth of the country.

"Census is not an essential exercise for now. Even if it is delayed by a year, there would be no harm," a senior official said.

The official said no final decision has been taken on when the first phase of the Census 2021 and NPR update would take place, but it is almost certain that it would not be held in 2020 due to the rising cases of the coronavirus.

The house-listing phase of the Census and the exercise to update NPR were scheduled to be carried out across the country from April 1 to September 30, 2020, but were postponed due to the COVID-19 outbreak.

"As the entire exercise needs the involvement of lakhs of officials and visit to each family, we can't undermine the health risk involved in it," the official said.

With a record single-day spike of 78,761 cases, the total coronavirus cases in India rose to 35,42,733, while the death toll climbed to 63,498 as on Sunday.

According to the earlier schedule, the census would have its reference date as March 1, 2021, and in the snow-bound areas of Jammu and Kashmir, Himachal Pradesh and Uttarakhand, it would be October 1, 2020.

"The COVID-19 threat is still looming large. The census and NPR are not in the priority list of the government as of now," another official said.

In March, when the coronavirus-induced lockdown was announced, the Registrar General and Census Commissioner of India was all set for the first phase of the census and updation of the NPR that was scheduled to begin from April 1.

Even though some state governments opposed the NPR update, all offered full support to the census exercise.

The census is the largest single source of a variety of statistical information on people of India which helps the State to chalk out various policies.

With a history of more than 130 years, this reliable, time tested exercise has been bringing out a veritable wealth of statistics every 10 years, including on the rich diversity of the people, and has become one of the tools to understand and study India.

The objective of the NPR is to create a comprehensive identity database of every usual resident in the country. The database would contain demographic as well as biometric particulars.

The NPR is a register of the usual residents of the country. It is prepared at the local (village and sub-town), subdistrict, district, state and national levels under provisions of the Citizenship Act, 1955 and the Citizenship (Registration of Citizens and Issue of National Identity Cards) Rules, 2003.

The data for NPR was last collected in 2010 along with the house listing phase of the Census 2011. Updating of this data was done during 2015 by conducting a door-to-door survey.

While updating the register in 2015, the government had asked details like Aadhaar and the mobile number of people.

This time, the information related to their driving licence and voter ID card may also be gathered, the officials said.

Though information regarding the place of birth of parents will be sought, it is up to the residents whether to respond to the question as it is voluntary.

For the NPR, a usual resident is defined as a person who has resided in a local area for the past six months or more or a person who intends to reside in that area for the next six months.

The law compulsorily seeks to register every citizen of India and issue a national identity card.

The demographic details required for every usual resident are name, relationship to head of household, father's name, mother's name, spouse's name (if married), sex, date of birth, marital status, place of birth, nationality (as declared), present address of usual residence, duration of stay at present address, permanent residential address, occupation and educational qualification.