Russia has built new troop barracks and plans more military infrastructure on a disputed Pacific island chain, angering Japan before potential high-level negotiations.
The defence ministry said by December 25 it would settle 188 soldiers and their families in four new military dormitories on the Kuril islands just north of Japan.
Russia is also building heated garages for more than 100 armoured vehicles there and will put up three more military dormitories next year.
The Japanese foreign ministry said it would file a note of protest over the construction on two of the southern islands, which were occupied by the Soviet Union at the end of the Second World War but are still claimed by Tokyo.
It said it had asked Russia in July to reduce military activity on the islands, where 3,500 of its troops are reportedly stationed.
Meanwhile, Japan will upgrade two helicopter carriers so they can launch fighter jets, giving it the first aircraft carriers since the Second World War, according to a defence plan approved Tuesday.
It will also purchase 147 US-made fighter jets in a record rearmament under pressure from Donald Trump to counter growing military activity by China and North Korea.
The latest move by Shinzo Abe to expand the military calls into question Japan’s commitment purely defensive capabilities under its post-war constitution.
China, which bolstered its territorial claims in the South Chinese Sea with its first domestically built aircraft carrier last year, voiced “strong dissatisfaction and opposition” to the rearmament and called on Japan to “adhere to a purely defensive policy”.
With the new dormitories, Moscow appeared to be setting a hard line before potential talks between Mr Abe and Vladimir Putin. The Kremlin said on Monday the two sides were discussing a visit by Mr Abe to Russia on January 21.
The Japanese foreign ministry said the expected negotiations would seek to solve the island issue and conclude a long-overdue peace treaty from the Second World War.
Mr Putin suggested at the Vladivostok economic forum in September that the two countries sign a peace treaty by the end of the year, but Japan has insisted on linking it to the territorial dispute.
While previous meetings have failed to yield results, there has been talk on both sides about resurrecting a tentative Soviet agreement to give back two of the four islands it took in 1945.
But Moscow would want to see significant concessions from Tokyo before moving ahead.
Foreign minister Sergei Lavrov warned on Monday that the Soviet draft agreement had predated the strong US military presence in Japan. Any deal would require that Japan recognise the islands are legitimately Russian and would be given “not as a return, but as a gesture of goodwill,” he added.
The Kremlin would be expected to demand a guarantee that US forces would never be deployed to the islands, which would also be a tough sell for the Japanese public.
Mr Abe has little he can reasonably offer Mr Putin, according to Alexander Gabuev of the Carnegie Moscow Centre. Even increased Japanese investment in Russia is unlikely due to US sanctions and the sluggish Russian economy.
“What are you getting in return? You don’t get massive economic help, you don’t get sanctions relief. What are you getting for giving away part of your territory?” he said. “The peace treaty is a piece of paper, we’ve lived without it for decades.”
In addition, a November poll found that three-fourths of the population remains against giving the islands to Japan. On Saturday, residents and officials on Russia’s far eastern island of Sakhalin staged a rare protest to demand the end of talks about returning the Kurils.
Mr Putin, whose approval rating has fallen from 82 per cent to 66 per cent following a controversial plan to raise the pension age this year, will be keenly aware of this sentiment.
Moscow may be stringing along Japan over the Kurils mainly as a bargaining chip with Beijing.
“Abe making circles around Putin is a good card for talking to the Chinese about investment,” Mr Gabuev said.