KABUL, July 21 (Reuters) - Afghanistan's Taliban movement threatened to kill two German hostages if its demand were not met by 07:30 GMT on Saturday, a spokesman for the militant group said. The Taliban is demanding release of all its members in Afghan prisons and the withdrawal of German troops from Afghanistan. "The Taliban leadership council has set 12:00 (local time) as deadline for the two German hostages. And if the deadline is not met, we will kill them," said spokesman Qari Mohammad Yousuf.