A 56-ft whale which became stranded on a beach in the Western Isles has died, rescuers said.

The mammal, believed to be either a sei or a fin whale, weighed two tones. It was discovered near Gerinish on South Uist at around 1pm on Monday.

British Divers Marine Life Rescue (BDMLR) volunteers attempted to refloat it but due to its weight, the volunteers were unsuccessful.

The Telegraph reported the volunteers had considered euthanasia but it was going to be a challenge, too, because the whale was so large.

"The animal has now died. Because of its size there was nothing that could be done. We just tried to keep it comfortable," Ali Jack, spokeswoman of the BDMLR, said on Tuesday.

"It's been quite emotional for all of the people involved, knowing it was absolutely certain that the animal was going to die... It's been quite hard because of the length of time it took to die."

Navigational error and sickness are both possibilities, Jack noted, adding it was "extremely unusual" if one of the sei whales species had come into such shallow waters.

Jack said the whale would undergo a post-mortem examination for BDMLR to try to find out what caused it to beach.