DUBAI (AFP) - Osama bin Laden has warned Al-Qaeda will kill Americans if the mastermind of the 2001 attacks on the United States, Khaled Sheikh Mohammed, is executed, in a tape Al-Jazeera television aired Thursday. The White House has declared its wish to execute (Khaled Sheikh Mohammed and his co-accused). The day the United States takes such a decision, it would be also taking the decision that any of you falling into our hands will be executed, bin Laden said in the message. Your friend at the White House is still walking in the footsteps of those before (him) in many important matters, including in escalating the war in Afghanistan and oppressing our prisoners that you are holding, beginning with the mujahid (resistor) hero Khaled al-Sheikh Mohammed, he added. US politicians have oppressed us and still do, especially by backing Israel, which occupies the land of Palestine, said the Al-Qaeda chief. The administration of US President Barack Obama is just weeks away from a landmark decision on whether to try Sheikh Mohammed and his four alleged co-conspirators in a civilian federal court or in a military tribunal.