The network of ocean currents which keep the Earth's climate stable could be about to collapse, scientists have warned.

In an open letter, 44 of the world's leading climate scientists say that key Atlantic Ocean currents - including the Gulf Stream - are on the brink of failure.

The scientists caution that the collapse of the Atlantic Meridional Overturning Circulation (AMOC) could lead to 'devastating and irreversible impacts' which will affect 'the entire world for centuries to come'.