Agra : The Taj Mahal, India's biggest tourist draw, might already be tilting and may even crumble or sink if the government does not restore it's ecological settings. Two noted historians have warned that the bed of the river Yamuna must be re-filled with water if the world's most famous monument, built on its banks is to be saved.

The Taj Mahal is celebrating its 350th anniversary this year. Built with high-quality white marble, it came up in the 17th century and is known as the Ultimate Monument of Love.

Dangerous tilts in its minarets, first noticed as early as 1942 and mentioned in various reports have continued to increase. They are caused by the dry river bed, Ram Nath a former head of Rajasthan University's history department, said.

The river forms an integral part of the monument's design. All historical records indicate that the Yamuna was always full and extensively used for transport. Even Shahjahan's body was brought to the Taj from the Agra Fort in a boat, he said.

Kagam Prasad Mathur, a former VC of Agra University, said :"The Yamuna used to be ful lto maintain the monuments balance. Now that the river bed is dry, the Taj is exposed to the elements."