No tsunami warning has been issued and there are no immediate reports of damage after a magnitude 5.0 earthquake struck eastern Japan.
A medium-strength earthquake has hit eastern Japan, NHK national television says, causing buildings to shake in Tokyo.
The quake occurred hours before the arrival of US President Donald Trump.
The epicentre of the earthquake was southern Chiba, about 60km southeast of the capital, the prefecture where Trump is due to play golf on Sunday with Prime Minister Shinzo Abe.
No tsunami warning was issued and there were no immediate reports of damage from the quake which the US Geological Survey measured as magnitude 5.
Trump and his wife, Melania, are due to arrive in Tokyo later in the day.