The Taliban has not issued a statement to confirm or deny that Mullah Akhtar Mansour is dead, but Afghan officials said the US attack was successful.
The Pentagon said an airstrike in a remote area of the Afghanistan-Pakistan border region targeted Mullah Akhtar Mansour, but his death has not been confirmed.
The release of the video comes just three days after the militant group declared the beginning of its fighting season — the time of year when the snow melts and Taliban fighters move to expand their territory.
Taliban leader Mullah Akhtar Mansour has been seriously wounded in Pakistan in a shootout between senior members of the Islamist movement, Taliban sources said, but the group's main spokesman dismissed their report as "baseless."
Attacks by Afghan troops on foreign soldiers have long been a major problem, but have declined in recent years. Wednesday's killings mark the first such attack since the Taliban's bitter leadership battle.
Mullah Muhammad Akhtar Mansoor dismisses reports of a peace process as "propaganda" and calls for unity among the Taliban, even as some of the group’s highest-ranking members dispute his ascension.
The Taliban distanced itself from ongoing peace talks with the Afghan government Thursday, amid reports that it has named a successor to deceased leader Mullah Omar.
The Taliban recently published an official biography of Mullah Omar, but next to nothing has been heard from the reclusive, one-eyed leader since the 2001 US invasion.
The attack has renewed fears about the Islamic State's ideological influence on some Afghan militants as the Taliban grow more divided.