When Russia launched its full-scale invasion of Ukraine in February 2022 it did more than redraw the map of Europe: it pulled at the frayed seam that has separated Tokyo and Moscow for decades. Since the end of WWII the two have been held in an uneasy diplomatic limbo. Cordial summits and shared economic projects - even President Putin’s love of judo - have been overlaid with the intractable dispute over the four southern Kuril Islands, known in Japan as the Northern Territories, and snatched by Russia at the end of WWII as a defeated Japan was left reeling by atomic bomb attacks on Hiroshima and Nagasaki.

Since 2022, however, Tokyo’s response to Moscow’s aggression has hardened Japanese policy in ways that both indicate solidarity with the West and create new vectors of friction with Moscow. Tokyo’s early approach to the invasion was notable for its swiftness and breadth. Within days Japan joined the United States and the European Union in sanctioning Russian individuals and entities, imposing asset freezes, trade restrictions and export controls aimed at eroding Moscow’s ability to sustain its war effort.

Over the next few years these measures expanded and ranged from targeted financial penalties to wider prohibitions on high-tech exports and bans on specific Russian products. In doing so Japan was working to align itself firmly with the western punitive response to the invasion, while preserving, for as long as possible, a distinctively Japanese emphasis on legal and economic precision.

That alignment has proven to be both symbolic and substantive as it signalled to allies that Tokyo’s post-war pacifism need not equal appeasement of aggression. This led to Japan limiting the avenues through which Russia could circumvent isolation even as both Tokyo and Moscow at times seemed to be working together on maintaining gas supplies from the Sakhalin 1 and 2 projects in Russia’s Far East.

Two-way sanctions

Sanctions have exacted a geopolitical cost – in both directions. Moscow has reciprocated in kind with its own blacklisting of Japanese officials and curtailing bilateral ties. In March 2025, Russia announced permanent entry bans on a group of Japanese citizens in a tit-for-tat poke at bi-lateralism, taking the shine off the post-Soviet rapprochement that once saw large Russian energy and infrastructure projects pitched to Japanese investors.

If the sanctions era has been one are of change though, the other is more physical and proximal: the militarisation of the Kurils and a deepening Moscow–Beijing axis.

Russia, in being pressed by Western isolation, has leaned into much publicised closer security ties with China involving joint patrols, infrastructure build-outs and the deployment of air and missile assets have transformed the islands into a de-facto frontier outpost of Moscow.

The islands are no longer just a dispute to be shelved.

Japanese analysts worry this moves the focal point of threat closer to Hokkaido and complicates Tokyo’s own leverage over the future return of the islands. In knock-on effect, the increased militarisation has hardened public and elite opinion in Japan against any hasty accommodation of Moscow across a wider front.

That reality poses a political conundrum for Tokyo’s new leadership. Sanae Takaichi, who only assumed the premiership in October 2025, arrived in office with a reputation for conservative nationalism but has so far signalled a mix of continuity and muscular pivoting.

Her early budgetary decisions and diplomatic posture suggest she intends to strengthen alliance ties, notably with Washington, and even with Taiwan, much to the annoyance of Beijing, while pursuing a domestic growth agenda that includes robust defence spending.

How she manages the Russia portfolio will be watched closely: does Tokyo double down on sanctions and deterrence, or does it seek to preserve residual channels of diplomacy in hopes of thawing the territorial dispute? Early signs point to the former and a hardening posture under Takaichi combined with careful hedging.

There are good political reasons for Takaichi - or any Japanese premier - to resist rapid rapprochement with Moscow.

Public sentiment towards Russia, never overly enthusiastic in the first place, soured after the 2022 invasion of Ukraine, and any perceived shift back towards amiability with Moscow could be politically very costly.

More importantly, Japan’s security environment has shifted: the thrust of Russian-Chinese cooperation and the unpredictable dynamics around Taiwan make Tokyo’s alignment with the United States and other democracies, even South Korea, a strategic imperative. For Takaichi, who has emphasised strengthening the US-Japan alliance and expanding Japan’s defence capabilities, sticking to coordinated sanctions while shoring up deterrence around the northern islands fits a long-held narrative of pragmatic realism.

Yet Japan’s sanctions, while punitive, are not total economic severance. Tokyo has to balance the immediate imperative of penalising aggression in Ukraine with longer-term national interests - energy security, access to markets in Eurasia, and the hope that a diplomatic path to the Northern Territories remains possible. In reality, Tokyo has been sat peeking over the parapet at the Russia-Ukraine-EU-US political shenanigans of the past few years from afar hoping it all sorts itself out without anyone expecting anything of Japan.

This explains why, even as Tokyo imposes export controls and tertiary sanctions, it has sometimes tried to keep a minimal diplomatic line open: enough to communicate and negotiate, but not enough to dilute the message to Moscow that its Ukraine campaign carries costs. Over time, though, as Russia moves ever closer to China by way of its no-limits relationship, the prospects for Japanese opinions to be heard fade away

For the islands of Etorofu-to, Kunashiri-to, Shikotan-to and Habomai-gunto themselves, the long-term picture is bleak. Moscow’s investments in military infrastructure, coupled with its willingness to use the Kurils as a staging ground for broader Pacific operations, have reduced the likelihood that Tokyo will ever recover the islands - in the near term or through drawn out negotiation.

Any Japanese move to seek accommodation from Russia - whether through a phased return, joint economic development, or confidence-building measures - now risks domestic backlash and looks less plausible given the Kremlin’s present posture. Possession of the islands is now a point of pride for many Japanese now that those with personal memories of a time spent living on the islands before 1945 are dying off.

As such, Tokyo is more likely to pursue a twin track approach in the form of intensifying deterrence in the region should Moscow ever take a shine to Hokkaido, along with building on existing levels of Western-alliance cooperation while in turn preserving non-political engagements with Russia to help keep future diplomatic links to the Kremlin from freezing over altogether.