After the 6-day war had been launched between Israel and Arab countries, Imam Khomeini issued a message wherein he called any relationship with Israel ‘haram’ or religiously prohibited. This message was in a way the main initiative that led to pervasive ‘Boycott Israel’ campaigns.
The message was issued on June 07, 1967 and reads as follows;
In the Name of God, the Beneficent, the Merciful
I have repeatedly invited Islamic states towards unity and brotherhood against instigators who seek to fuel discord among Muslims and the Islamic states; to enslave and humiliate our dear countries under colonialism and exploit their spiritual and materialistic resources.
I have repeatedly warned governments, the Iranian government in particular, against Israel and its dangerous mercenaries.
This source of corruption, which has been placed in the heart of Islamic countries with the support of major powers and its roots of corruption, threaten the Islamic countries day after day. This source should be eradicated through the efforts of Islamic countries and the great Muslim nation. Israel has launched an armed revolt against Islamic countries and it is obligatory for the Islamic states to eliminate it.
Helping Israel by way of selling weapons and explosive materials or selling oil is haram; it is an act of disobeying Islam.
Relations with Israel and its mercenaries, whether commercial relations or political ones, are haram and an act of disobeying Islam; Muslims should avoid using or purchasing Israeli goods.
I ask God for the victory of Islam and Muslims.
“May peace be upon him who follows guidance.” Quran [20:47]
Ruhullah Mousavi Al-Khomeini