Clean-up workers Monday started removing a layer of grey ash that spread across a city in southern Japan after a volcano erupted at the weekend, spewing a plume 5,000 metres into the air.

Kagoshima city mobilised more than 60 street sweepers as well as water-spraying vehicles to remove ash that coated the streets, officials said.

The eruption of the 1,117-metre (3,665-foot) Mount Sakurajima overlooking the city happened on Sunday afternoon, spewing the highest ash plume from the volcano since an eruption in 2000.

Television footage showed the mushroom-shaped grey plume shooting upwards against the backdrop of a clear blue sky.

A large amount of volcanic ash fell in the northern and central parts of the city, causing a delay in train services and temporary poor visibility, forcing car drivers to use their headlights.

Residents turned to masks and umbrellas to protect themselves against the ash cloud, but there were no reports of injuries or damage, city officials said.

"The volcanic activity had been subdued by Monday morning," a local meteorological agency official said.

"There is no sign of large scale eruptions in the near future, but we have not yet lifted a two-kilometre (1.2-mile) no-go zone just in case."

The eruption also caused a small amount of lava to run down the side of the crater.

It was the highly active volcano's 500th eruption this year. Japan is a seismically active country with regular earthquakes and eruptions from volcanoes that dot the archipelago.

Kagoshima city is about 950 kilometres southwest of Tokyo.