'Akilisi Pohiva was in Auckland last month before returning to Tonga briefly.
The prime minister told local media he's been advised by his doctor to avoid any intensive mental activity.
The cause of Mr Pohiva's ill-health has not been revealed.
Meanwhile Matangi Tonga reports Mr Pohiva saying King Tupou VI was right to say, during the opening of parliament last week, that the government has no vision for economic development.
Mr Pohiva says his government has failed to spell out its plan clearly.
On the matter of the public consultations over six controversial bills the government had wanted pushed through under urgency, Mr Pohiva accused the Speaker of troublemaking, and said his Cabinet is moving to impeach him.
Photo Loop Tonga
Source:
RNZI