New Delhi, July 23 - Nandan Nilekani took charge as the chairman of the Unique Identification Database Authority of India Thursday and started work on the government's ambitious project to provide a single identity number and card to each of the country's 1.17 billion people.

Nilekani, who met with reporters briefly after assuming office at Yojana Bhavan, the headquarters of the Planning Commission here, said the main task of the authority would be to create a database that will help in issuing unique identity cards.

'This will be a nationwide system of authentication,' said the 54-year-old co-founder of Infosys Technologies, who was personally selected by Prime Minister Manmohan Singh to head the project with the rank of a cabinet minister.

'Identity is important for everyone, especially for the poor. Getting an identity is a tough job. We will provide a database of residents. We will have a very simple database in biometrics. We will only have very basic information,' he said.

Nilekani said that the authority will not issue the biometric cards itself -- but the database it is creating will help government agencies to undertake that task.