Today members of Afghanistan's Wolesi Jirga (lower house of the National Assembly) addressed this statement. Dr. Abdul Kabir Ranjbar, representative of Kabul and head of the Democratic Party of Afghanistan, is reported to have stated that attacking U.S. interests in Afghanistan from abroad would be a violation of the territorial integrity of Afghanistan and a breach of international law. Several other deputies made similar statements, though I do not yet have the texts. I would welcome help from anyone who can get them.
So far I have found no comment from the National Front, a group in the Afghan National Assembly that has received some assistance from Iran. The Afghan government and the Iranian embassy in Kabul declined to comment. The Ambassador of Iran to Afghanistan, Muhammad Reza Bahrami, was removed from his post by Tehran soon after General Jafari's statement. Bahrami has represented Iran in Afghanistan in various capacities for twenty-three years.
Update: I received from Kabul the text in English of a Tolo TV broadcast on this subject:
Text of report by Afghan independent Tolo TV on 18 September 2007
[Presenter] Iran has warned that it will target US troops in Afghanistan and Iraq if America attacks Iran.
[Passage omitted: comments by a senior commander of the Iranian Revolutionary Guards Corps]
[Correspondent] A number of MPs describe as irresponsible the recent remarks by the commander of the Revolutionary Guards Corps, saying that it is an excuse for Iran to interfere in the internal affairs of Afghanistan and help the Afghan armed insurgents.
[Kabir Ranjbar, MP from Kabul Province] [The military forces of] any other country present in Afghanistan act in line with the constitution and other laws of Afghanistan. Attacking those [foreign] forces means invading Afghan soil. I do not consider this an attack on the Americans. From the legal point of view, it is an absolute violation of inter-governmental relations, and of good neighbourly values and principles with Iran.
[Ahmad Shah Khan Achakzai, MP from Kandahar Province, in Pashto] Relations between Iran and America have been bad for a long time. I believe this is only an excuse by the Iranians.
[Jamil Karzai, MP from Kandahar Province, in Pashto] First, if we take a look back, relations between Iran and America have not been good for the past 15 to 20 years, since the establishment of the Islamic government in Iran. They are not on good terms. The president of Afghanistan has offered to mediate between the two countries, if possible.
[Correspondent] America has stressed diplomatic ways of addressing the Iranian nuclear problem, but has not ruled out the possibility of resorting to military options. We tried to contact the Afghan Foreign Ministry and the Iranian embassy in Kabul for their comments on the issue, but they were not available for comments.
Further update from the comments: On September 19, Iranian Ambassador to Kuwait Ali Jannati stated that "in case of any military attack on Iran, the country will target all U.S. military bases used for Washington's attack." He called such an attack "unlikely," and added:
Iran only attacks those military bases used for launching military assault against it. Tehran believes that the countries of the region would never let the U.S. use their soil to attack Iran.This appears to mean that, if the U.S. uses bases in Iraq or Afghanistan to attack Iran, Iran will retaliate against U.S. bases in those countries, but that otherwise it will respond in other ways.