Saudi Arabi's foreign minister on Sunday accused Iran of interfering in Iraq's internal affairs, during his meeting with British Foreign Secretary Philip Hammond.
"Iraq's problem is religious conflicts caused by the Iranian interference," Foreign Minister Adel al-Jubeir told a press conference following a Gulf Cooperation Council's foreign ministers' meeting.
"It is unacceptable that Iran is in Iraq and sending Shia militants to train people, causing sectarianism," he added.
Saudi Arabia accuses Shia Hezbollah-Lebanon's most powerful military force-of serving as a proxy for Shia Iran and of hijacking Lebanese policymaking.
Since 2012, Hezbollah has sent fighters to Syria to support the Assad regime, while Riyadh remains one of Assad's staunchest foes.
Hezbollah, for its part, criticizes Saudi military intervention in Yemen, where Riyadh is leading a fierce campaign against the Shia Houthi militant group, which overran much of the country in 2014.
One day after Riyadh cut military aid to the Lebanese army, the six-nation Gulf Cooperation Council (GCC)-of which Saudi Arabia is a leading member-declared its "full support" for the move.
In a veiled reference to Iran, the GCC (which also includes Qatar, the United Arab Emirates, Kuwait, Bahrain, and Oman) voiced its "deep regret" that Lebanese policymaking had become "hostage to the interests of external powers".
The moves came after Beirut declined to condemn an attack on the Saudi Embassy in Tehran by Iranian protesters, who ransacked the embassy in early January to protest the execution days earlier of a prominent Shia cleric by Saudi authorities.
Following the embassy incident, several Arab countries-led by Saudi Arabia-cut diplomatic relations with Iran.
Asked whether Saudi Arabia was involved in Iran's decision not to send pilgrims to the Hajj this year, Al-Jubeir said "the responsibility belongs to Iran".
"Iran is responsible for blocking the Hajj pilgrimage for their citizens this year. Saudi Arabia wants every Muslim, including Iranians, to come to our land for the Hajj pilgrimage," al-Jubeir said.
An Iranian official said Sunday that Iran will not send pilgrims to Hajj this year due to "Saudi restrictions".
Al-Jubeir said the Iranian delegation did not sign the agreement on allowing Hajj pilgrimages, "although we met most of their requirements".
Saudi Arabia officially cut its ties with Iran in January after its diplomatic missions in Tehran and Mashhad were attacked by Iranian protesters following the execution of a prominent Shia imam-Nimr al-Nimr-by Saudi authorities.
