Japan's former emperor Akihito, who abdicated last year, collapsed and lost consciousness at his residence yesterday.

When the 86-year-old fell, Empress Emerita Michiko was nearby and pressed an emergency alarm at the Tokyo Imperial Palace.

Akihito was still unconsciousness when the doctor arrived but was snoring. He was taken to his bedroom for recuperation.

Akihito 'had an MRI examination Thursday morning but doctors found no abnormalities', a palace official said, adding doctors would continue to monitor his condition.

Japan's former emperor Akihito, who abdicated last year, collapsed and lost consciousness at his residence on Wednesday (pictured: with Empress Emerita Michiko last year)

When the 86-year-old fell, Empress Emerita Michiko (left) was nearby and pressed an emergency alarm at the Tokyo Imperial Palace

Akihito, who now holds the formal title of emperor emeritus, had breakfast as normal on Thursday, Kyodo news agency said.

The Tokyo Imperial Palace

In July, Akihito suffered temporary cerebral anaemia, a condition involving insufficient blood supply to the brain.

He had fallen ill while having his dinner but made a swift recovery.

The former monarch has previously had surgery for prostate cancer and heart problems.

His 85-year-old wife, Empress Michiko, had surgery for early stage breast cancer in September and the palace said in December she had been unwell and lost weight since.

Akihito shocked the country in 2016 when he signaled his desire to step down after nearly three decades in the job, citing his age and health problems.

He abdicated at the end of April in 2019 and his son Emperor Naruhito ascended the Chrysanthemum Throne the next day.