A vast slice of Antarctic ice is about to break away from the continent.

A huge crack across the Larsen C ice shelf has widened in the past few months, and a vast iceberg is expected to break off.

If it does, it would be one of the ten biggest icebergs ever.

But glaciologist Professor Adrian Luckman said it would be wrong to finger climate change as the reason.

"This is a natural action of a rift that has been there for many years and the impact on sea levels will be a long time in coming."