Japan lifted a warning on Thursday, that a megaquake potentially causing colossal damage and loss of life could strike, with the government telling people to go back to their normal activities.

The week-old alert that such a catastrophe might hit the archipelago of 125 million people prompted thousands to cancel holidays and stock up on essentials, emptying shelves in some stores.

Disaster management minister Yoshifumi Matsumura said as he announced the lifting of the advisory that the people of Japan are free to go back to normal lifestyles. 

However, he said people should not forget measures such as securing furniture, ensuring family members know the location of evacuation shelters, and stockpiling emergency foods.

Matsumura told reporters that the special call for attention ended but doesn't mean the risk of a major earthquake has been eliminated. 

He therefore encouraged people to be mindful of the daily precautions and remain vigilant for a megaquake that can happen anytime.

Japan's weather agency said last Thursday the likelihood of a megaquake was "higher than normal" following a magnitude 7.1 jolt that day that injured 15 people.

That was a particular kind of tremor known as a subduction megathrust quake, which has occurred in pairs in the past and can unleash massive tsunamis.