Kabul: Allegations over Russia and Iran's deepening ties with the Taliban have ignited concerns of a renewed "Great Game" of proxy warfare in Afghanistan that could undermine US-backed troops and push the country deeper into turmoil.
Moscow and Tehran insist their contact with insurgents is aimed at promoting regional security, but local and US officials who are already frustrated with Pakistan's perceived double-dealing in Afghanistan have expressed bitter scepticism.
Washington's long-time nemesis Iran is accused of covertly aiding the Taliban, and Russia is back to what observers call Cold War shenanigans to derail US gains at a time when uncertainty reigns over President-elect Donald Trump's Afghanistan policy.
"(Russia's) narrative goes something like this: that the Taliban are the ones fighting Islamic State," top US commander in Afghanistan John Nicholson said recently, denouncing the "malign influence" of external powers.
"This public legitimacy that Russia lends to the Taliban is not based on fact, but it is used as a way to essentially undermine the Afghan government and the NATO effort and bolster the belligerents.
"Shifting to Iran, you have a similar situation. There have been linkages between the Iranians and the Taliban."
Russia has officially provided military helicopters for Afghan forces, but simultaneously propped up the Taliban with arms, official and insurgent sources say.
"We are particularly concerned about loads of Russian-made weapons recently seized from areas on the border with Tajikistan," a senior Afghan security official told AFP.
"Cross-border support for the Taliban will further complicate the security situation in Afghanistan's north."
A Taliban commander told AFP the Russian support had helped the insurgents overrun the northern city of Kunduz in October for the second time in a year.
Taliban representatives in recent months have also held several meetings with Russian officials in Tajikistan and Moscow, sources say.
"No country should be in touch with destructive groups who are the enemies of Afghanistan. This shows disrespect towards the victims of war," interior ministry spokesman Sediq Siddiqi told AFP.
"We ask Russia and Iran to work with Afghans to defeat terrorism."