Google maps are not considered "authentic" since they are not charted by the government, the country's top surveyor has said.

Swarna Subba Rao, the Surveyor General of India, said yesterday that maps prepared by the Survey of India, a 250- year-old institute in Dehradun, were used for vital infrastructure projects.

"Google maps are not authentic. They are not produced by the government so they don't stand any authentication," he said.

The head of the institute which has the mandate to prepare maps for defence purposes said many people used Google maps "for low end" applications.

"The maps produced by the Survey of India are used for serious applications," he said, responding to a question at an event organised to release a commemorative stamp to mark 250 years of the institute.

The Survey of India's topography maps are needed for "very accurate and engineering quality data" essential for something like a new rail line or a canal, Rao said.

The Survey of India falls under the Department of Science and Technology.

DST secretary Ashutosh Sharma, however, added that it would be wrong to disregard satellite mapping, as the maps prepared by the Survey of India and companies such as Google served different purposes.

Manoj Sinha, Minister of State for Communication, said the Survey of India had the "distinct honour" of printing India's first postage stamp and the first copy of the Constitution of India.

He added that any developmental work could only start after proper survey and mapping had been done.