Deadly Hurricane Matthew has been described as the “most dangerous storm in living history” as the death toll now stands at more than 800.

The devastating storm has left more than 800 people dead and tens of thousands homeless as it rampaged across Haiti before heading for the US.

US President Barack Obama urged people to take Hurricane Matthew seriously because if they didn’t, they could be gambling with their own lives.

Most people followed warnings to evacuate from danger zones in the Carolinas, Florida and Georgia. But with the storm now reaching its peak, anyone who has not already left has been told it is too late and they must now batten down the hatches and hope for the best.

Mr Obama said: “I just want to emphasise to everybody that this is still a really dangerous hurricane, that the potential for storm surge, loss of life and severe property damage exists.” He urged people to follow the instructions of local officials until the danger had gone.

Britain has promised to send £5m in aid to Haiti to help in the immediate aftermath of Hurricane Matthew. The Navy is taking helicopters, bulldozers and vehicles which can get to affected areas with clean water. It is also taking surgical teams who can use onboard operating theatres to treat the injured.

So far, the US has not been as badly affected as its poorer neighbour, Haiti, but northeast Florida in particular is still not out of the worst, with warnings of significant flooding to come.

The director of the Federal Emergency Management Agency, Craig Fugate, said it was vital that people further up the coast in Florida weren’t given a false sense of security by the fact the damage so far has been relatively light considering the force of the hurricane.

He said: “People should not be looking at the damage they’re seeing and saying this storm is not that bad. The real danger now is still storm surge, particularly in northern Florida and southern Georgia.”

Mr Fugate said there had not been the potential for so much damage since the 1800s.