NEW DELHI • The Taj Mahal will need nine years of mud packs to remove yellow stains from its white marble walls caused by air pollution.

Archaeologists said the lengthy period is needed to properly and safely clean particles from the four minarets and the main dome of the famed monument.

The authorities have taken numerous steps in recent years to protect the 17th-century monument from pollution coming from the busy city of Agra nearby, including banning local coal-powered industries.

The mud pack cleaning was announced last year, followed by a local ban on the common practice of burning cow dung for fuel in order to reduce the carbon deposits on the Taj's walls.

The Times of India newspaper outlined the action plan by the authorities after submitting a Right To Information request to access government documents.

The Taj - India's top tourist attraction - was built by Mughal emperor Shah Jahan as a tomb for his beloved wife Mumtaz Mahal, who died while giving birth in 1631.

AGENCE FRANCE-PRESSE