Hawaii's erupting Kilauea volcano could take many more years before it fully empties its underground reservoirs of molten lava, United States Geological Survey (USGS) scientists gravely warned.

Scientists fear the lava released by Kilauea so far has not even scratched the surface of its hidden magma reserves.

When asked if the Hawaii volcano’s chambers will empty any time soon, the US agency admitted there is no accurate way of knowing.

The USGS said: “We're not exactly sure how much magma is stored beneath the summit.