Russian President Vladimir Putin speaks during an interview in Sochi, Russia, on Tuesday. (Alexei Nikolsky/AP)

Russia will ship small arms to Afghanistan next month, a top diplomat announced Wednesday, expanding Moscow’s role as the United States winds down its military mission and the Taliban and other militants appear to gain ground.

Russia is concerned that extremist factions in Afghanistan could spill over the northern borders into former Soviet Central Asian countries where Russia has a major military presence.

The decision also bolsters Russia’s role in a nation that was a Cold War-era ally and the scene of Moscow’s disastrous military intervention in the 1980s.

[Russia shares intelligence with Taliban to undercut the Islamic State]

It comes at a time when Russia is expanding activities outside its borders, conducting wide-ranging airstrikes in Syria and pushing for a bigger international role to resolve a series of conflicts in Afghanistan, Syria and elsewhere.

The shipment of small arms will take place in February, but Russia has no plans to ship other weapons, said President Vladimir Putin’s special envoy for Afghanistan.

“For now this is quite sufficient,” the diplomat, Zamir Kabulov, told the Interfax news agency.

The United States and its allies have withdrawn most of their military presence over the past year, leaving Kabul searching for new partners in its efforts to fend off the Taliban.

Russia has trained Afghan air force pilots in the years since a U.S.-led alliance toppled the Taliban after the Sept. 11, 2001, terrorist attacks. But Afghan officials in recent months have pushed Moscow to increase its aid.

Russia has sent arms to Kabul after being paid by intermediaries, including India and the United States. Last fall, a series of Afghan officials visited Moscow to request helicopter gunships and heavy weaponry.

In 2011, the Defense Department signed a contract with Russia’s arm sales agency, Rosoboronexport, to supply the Afghan military with Russian-made helicopters. The agency had been hit with Western sanctions after Russia’s military incursion into Ukraine, but in November it was granted a U.S. exemption to maintain the helicopters.

Putin said in October that the situation in Afghanistan was “close to critical” and has signaled an openness to increasing his nation’s role there.

But any significant escalation would come with extreme caution from Moscow, where memories of Afghanistan as a graveyard for Soviet troops remain powerful.

The 1979-1989 war there cost thousands of Soviet military lives and was a factor in the collapse of the Soviet Union. The Soviet army battled insurgent forces that were backed by the West and attracted Islamists fighters such as Osama bin Laden.

Even now, military casualties are one of the most politically sensitive subjects in Russia.

Last month, Russia announced that it had begun limited information exchange with the Taliban in order to combat the Islamic State, which has a growing presence in Afghanistan. The unusual arrangement came as Russia grows concerned that the Islamic State could pose a domestic terrorism threat.

Read more:

Russia is a new front for Islamist militants

NATO versus Kremlin in Syria

Today's coverage from Post correspondents around the world