Seen speaking to a group of Taliban fighters, Mullah Hidayat Allah Akhhond referred to recent events in Iraq as part of his call to arms.
"We urge you to resist the foreign occupation of the lands of Palestine, Chechnya, Afghanistan and Iraq," he said.
"One could wonder what Iraq has done wrong," he went on. "They have not been able to find any weapons of mass destruction, and there is no Bin Ladin in Iraq, so why is it occupied?"
The senior Taliban commander went on to urge Afghans to resist attempts to drag them into ethnic conflict and criticised US-backed Afghan president Hamid Karzai.
This was the first public broadcast by any representative of the Taliban, in contrast with the relatively frequent al-Qaida tapes, and analysts said it was an attempt to show that Afghanistan's former ruling militia were still a fighting force to be reckoned with.
Habib Hakimi, a writer based in Kabul, told Aljazeera that after two years of war the Taliban wanted to prove that they had not been routed by assaults from the US and newly formed Afghan armies.
"It may be a disguised call for aid from Pakistan and Saudi Arabia"
"It may be a disguised call for aid from Pakistan and Saudi Arabia," he said, citing the erstwhile allies of the Taliban.
It is thought that fighters and supplies are filtering through Pakistan's porous border with Afghanistan.
Hakimi said that the situation in Iraq was showing that the US was not invincible, which was giving heart to fighters resisting American forces elsewhere, as well as Muslims fighting the Russian and Israeli armies.
In the tape, Akhond claimed that the Taliban had recaptured areas of Afghanistan, naming the town of Dayd Chopand and other parts of the southeastern province of Zabul.
The former head of Pakistani intelligence Hamid Gul has said the US has made a mistake in invading Afghanistan, as it is a very difficult area to control.
"The Taliban is still popular in Afghanistan, and there are people who feel nostalgia for the days of their rule, when the country was more peaceful and stable," he said.