Osama bin Laden's killing amounts to a "big failure" for Washington, Iranian defence minister Ahmad Vahidi said on Wednesday, as he cast doubt on the US decision to bury the al-Qaeda chief at sea.
"The United States says it has achieved success with the death of bin Laden, but .... it actually is a big failure," Vahidi said, quoted by Iran's state news agency IRNA.
"The United States forced 10 years of war on three countries (Iraq, Afghanistan and Pakistan), left a million people dead and spent more than 1,000 billion dollars to kill one person."
Vahidi spoke of "ambiguities" over bin Laden's death.
The Americans "said they threw his body in the sea. Why did they not allowed an independent expert to examine the body to say if it was bin Laden or not?" the defence chief asked.
He also echoed what other Iranian officials have said since bin Laden's death announced on Sunday night that there was "no longer any excuse for the US to stay in the region."
Shiite Iran has always considered Al-Qaeda as a Sunni ultra-radical and anti-Shiite threat to its security.
But the Islamic republic has regularly criticised the presence of US-led Western forces in Afghanistan, saying it prevented any negotiated settlement of the Afghan conflict.
Tehran also regularly denounces the presence of US forces in Arab states of the Gulf, calling it a source of regional tension.