Saudi Arabia and the Islamic Republic of Iran reached an agreement on the participation of Iranian pilgrims in the Hajj. Ritual visits to Mecca is one of the five pillars of Islam. Every believer must make the pilgrimage at least once in your life.
In 2016, Iran has decided to boycott the Hajj for safety reasons. Tehran laid on the government of the Kingdom of responsibility for the stampede that occurred during a pilgrimage 2015. Then killed almost 2.400 believers, including more than 460 of Iranian citizens.
After that, the Supreme leader of the Islamic revolution Ayatollah Ali Khamenei accused the king Salman that the Shrine became his instrument of profit. He urged Muslims to deprive Saudi Arabia of control over Mecca and Medina.