The trillion-tonne slab of ice, named A23a, now poses a risk to millions of marine animals.

A23a – the world’s largest iceberg – is stuck 80 kilometres off the small British overseas territory of South Georgia- which is home to millions of penguins – seals and other marine life.

Even finding the iceberg can be a challenge.

“The South Georgia and South Sandwich Maritime Zone is enormous, as it’s 1.2 million km² of ocean – It’s a vast area,” Laura Sinclair Willis, South Georgia Chief Executive said.

But A23a isn’t small either.

It’s almost four times the size of Canberra – at more than 3100 square kilometres.

It’s nearly 300 metres tall and it weighs around one trillion tonnes.

There are concerns the melting ice could force the food for millions of marine animals deeper underwater.

The megaberg’s movements, a reminder of Antarctica’s rapidly melting ice are caused by global warming.

In 1986, A23a broke off from Antarctica but remained aground in the Weddell Sea until 2020 when it started moving north.

Five years on, the huge slab of ice has, for now, stopped in its tracks.