"These claims are absolutely false," Zamir Kabulov, head of the Russian foreign ministry's department responsible for Afghanistan and the Kremlin's special envoy in the country, told RIA Novosti state news agency.
"These fabrications are designed, as we have repeatedly underlined, to justify the failure of the US military and politicians in the Afghan campaign. There is no other explanation."
NATO's Supreme Allied Commander, US General Curtis Scaparrotti, who also heads the US military's European Command, told lawmakers in Washington on Thursday that he had witnessed Russia's influence grow in many regions, including in Afghanistan.
In a statement to the Senate Armed Services Committee, Scaparrotti said Moscow was "perhaps" supplying the Taliban.
In February General John Nicholson, the US commander of NATO forces in Afghanistan, testified that Russia is encouraging the Taliban and providing them with diplomatic cover in a bid to undermine US influence and defeat NATO.
Kabulov in 2015 said that Russia was exchanging information with the Taliban and saw shared interest with them when it comes to fighting the ISIS.
Russia considers the Taliban a terrorist group and it is banned in the country, along with the ISIS.
Taliban fighters on Thursday captured Afghanistan's strategic district of Sangin, where US and British forces suffered heavy casualties until it was handed over to Afghan personnel.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)