Speaking in a rare television address on Wednesday, Japan's Emperor Akihito expressed his condolences to the victims of the tsunami.
As fears grew over radiation leaks at a nuclear power plant damaged in the disaster, the 77-year-old urged his people not to give up.
"I am deeply concerned about the nuclear situation because it is unpredictable," said the royal.
"With the help of those involved I hope things will not get worse."
He went on to thank those involved in relief operations, including foreign governments.
Friday's earthquake-turned-tsunami has devastated Japan's north east coastline and the death toll is estimated to be over 10, 000.
"We don't know the number of victims, but I pray that every single person can be saved," Akihito said.
Stoic survivors bravely try to mend shattered lives
Photo: © TBS