The war in Afghanistan has split the policies of the Iranian government. The minority conservatives are arming and equipping Taliban, al Qaeda and pro-Iranian groups in western Afghanistan. The conservatives control the courts and the military. The majority, which control the rest of the government, are opposing the conservatives, but  without much effect. This mucking about in western Afghanistan is dangerous, as most Afghans are Sunni Moslems, which Iranians are Shia. The Taliban persecuted Afghan Shias when they were in power. Afghans in general realize that half the Afghan population speaks a dialect of Iranian and, historically, western Afghanistan has, from time to time, belonged to one Iranian empire or another. It's quite likely that Afghan groups will take the Iranian goodies, and then ignore the Iranians.