Putin`s snap trip to Sakhalin Island, whose southern half was controlled by Japan in the 19th century, will primarily cover energy issues, his spokesman Dmitry Peskov told Russian news agencies.
"The visit will be devoted to issues concerning gas," said Peskov.
Putin will be discussing "the completion of a gas pipeline and its hook-up to a local thermal power plant," the spokesman said.
Peskov did not mention the Japanese earthquake but the visit comes amid mounting concern among the residents of Sakhalin and Russia`s Far East region about the risk of radiation from Japan`s quake-damaged nuclear plant.
Earlier this week, President Dmitry Medvedev instructed the Russian government to come up with an emergency rescue plan for Japan that included new liquefied natural gas and coal shipments.
On Thursday, the Russian government also volunteered to assist Japan in preventing a release of radiation at its damaged Fukushima nuclear power plant.
Previous visit by top Russian officials have provoked concern in Japan due to the two sides` simmering dispute over the nearby Kuril Islands, which the Soviet army seized in the dying days of World War II.
Russia has vowed to build up the Kurils` defences and denounced Japanese claims on the chain.
The Kurils row came to a boil in November when Medvedev became the first Russian leader to visit one of the four islands in the Russian-controlled portion of the chain.
But the dispute appears to have been subsumed by the nuclear crisis, which Russian officials have been monitoring on a daily basis with growing alarm.
Medvedev noted Thursday that "what has happened in Japan is a colossal national disaster, a catastrophe." (*)