Kolkata: India has not been affected by a massive oil spill in the waters of Sundarbans delta on the Bangladesh side, forest department officials said.

"Our staff has been patrolling the bordering region for the last 3-4 days. No such effect has been seen so far on the Indian side," Sundarbans Tiger Reserve's field director Soumitra Dasgupta told PTI.

Last week, a tanker and another vessel collided on the Bangladesh side of the Sundarbans delta resulting in the spilling of more than 3,50,000 litres of furnace oil into the waters.

Formed by the rivers Ganga, Brahmaputra and Meghna, the world's largest delta of Sundarbans is spread across India and Bangladesh.

A UNESCO World Heritage site, it is an archipelago of more than a hundred islands famous for its mangrove forests and several endangered species like the Royal Bengal Tiger, Ganges and Irawadi dolphins.

Dasgupta said wildlife on the Indian side is safe from the spill.

They have alerted disaster management team and BSF personnel to take precautionary measures.

When asked as to how far the oil spill area was located from the Indian side, he said, "We do not know exactly but it is not less than 200 km".