The killing of Al-Qaeda leader Osama bin Laden by US forces will give "a new impetus" to the fight against foreign "invaders" in Afghanistan, the Taleban said in a statement.
"The Islamic emirate believes the martyrdom of Sheikh Osama bin Laden will give a new impetus to the current jihad against the invaders in this critical phase of jihad," an email statement released by spokesman Tariq Ghazniwal said.
The comment was the first substantive reaction by the Taleban in Afghanistan to this week's assassination of bin Laden in Pakistan.
They had previously only said it was "premature" to comment on the death in a statement Tuesday which cast doubt on whether the killing had actually taken place.
But in its latest statement, the Taleban warned that the US and other Western countries with troops in Afghanistan must not "wallow in this optimism" created by the death of bin Laden.
"The sapling of jihad has always grown, spruced and reached fructification through irrigation by pure blood," it added.
"The martyrdom of a martyr leads to hundreds more to head to the field of martyrdom and sacrifice."
There are currently around 130,000 international troops in Afghanistan, around two-thirds of them from the US, fighting insurgents including the Taleban. Foreign combat troops are due to withdraw from Afghanistan by 2014.
The Taleban comments came as Al-Qaeda confirmed bin Laden's death but warned that those rejoicing his killing would have their "blood mixed with tears" and vowed the movement would live on.
The US has said it is on alert for security threats in the wake of the killing in Abbottabad by US commandos.
President Barack Obama has said that bin Laden's death proved America would never fail to bring terrorists to justice, saying "when we say we will never forget, we mean what we say."
On Friday, Obama was to hold a private meeting with members of the elite commando team who carried out the risky helicopter-borne raid on the fortified compound where bin Laden had been hiding.