During the Yemeni civil war, Saudi Arabia led an Arab coalition of nine nations from the Middle East and parts of Africa in response to calls from the internationally recognized pro-Saudi president of Yemen Abdrabbuh Mansur Hadi for military support after he was ousted by the Houthi movement due to economic and political grievances, and fled to Saudi Arabia.
Nations such as the United Kingdom and the United States support the Saudi Arabian-led intervention in Yemen primarily through arms sales and technical assistance. France had also made recent military sales to Saudi Arabia. MSF emergency coordinator Karline Kleijer called the US, France and the UK part of the Saudi-led coalition, which imposed the weapons embargo and blocked all ships from entering Yemen with supplies. Human rights groups have criticized the countries for supplying arms, and accuse the coalition of using cluster munitions, which are banned in most countries. Oxfam pointed out that Germany, Iran, and Russia have also reportedly sold arms to the conflicting forces. Tariq Riebl, head of programmes in Yemen for Oxfam, said, "it's difficult to argue that a weapon sold to Saudi Arabia would not in some way be used in Yemen," or "if it's not used in Yemen it enables the country to use other weapons in Yemen." Amnesty International urged the US and the UK to stop supplying arms to Saudi Arabia and to the Saudi-led coalition.
It called on the international community, including the United States and United Kingdom to stop "providing arms that could be used in the conflict in Yemen". On August 3, 2019, a United Nations report said the US, UK and France may be complicit in committing war crimes in Yemen by selling weapons and providing support to the Saudi-led coalition which is using the deliberate starvation of civilians as a tactic of warfare.
Arab coalition
Allegations of Iranian involvement
The coalition accused Iran of militarily and financially supporting the Houthis. On 9 April US secretary of state John Kerry said there were "obviously supplies that have been coming from Iran", with "a number of flights every single week that have been flying in", and warned Iran to stop its alleged support of the Houthis. Iran denied these claims.
Anti-Houthi fighters defending Aden claimed they captured two officers in the Iranian Quds Force on 11 April, who had purportedly been serving as military advisers to the Houthi militias in the city. This claim was not repeated. Iran denied presence of any Iranian military force.
According to Michael Horton, an expert on Yemeni affairs, the notion that the Houthis are an Iranian proxy is "nonsense".
According to Agence France-Presse, a confidential report presented to the Security Council's Iran sanctions committee in April 2015 claimed that Iran had been shipping weapons to the Houthi rebels since between 2009 and 2013. The panel further noted the absence of reports of any weapon shipments since 2013.
On 2 May, Abdollahian said that Tehran would not let regional powers jeopardize its security interests.
According to American officials, Iran discouraged Houthi rebels from taking over the Yemeni capital in late 2014, casting further doubt on claims that the rebels were fighting a proxy war on behalf of Iran. A spokeswoman for the US National Security Council said that it remained the council's assessment that "Iran does not exert command and control over the Houthis in Yemen."
On 6 May, Iran's supreme leader, Ayatollah Ali Khamenei, said, "The Americans shamelessly support the killing of the Yemeni population, but they accuse Iran of interfering in that country and of sending weapons when Iran only seeks to provide medical and food aid."
On 26 September 2015, Saudi Arabia alleged that an Iranian fishing boat loaded with weapons, including rockets and anti-tank shells, was intercepted and seized in the Arabian Sea, southeast of the Omani Port of Salalah, by Arab coalition forces. In May 2019, Houthi militias launched two attacks to two pumping stations managed by Saudi Aramco. Anas AlHajji, an oil expert, said that such an attack is planned to damage the said pipelines as they replace the Strait of Hormuz's oil passages.
United States
In March 2015, President Barack Obama declared that he had authorized US forces to provide logistical and intelligence support to the Saudis in their military intervention in Yemen, establishing a "Joint Planning Cell" with Saudi Arabia. This includes aerial refueling permitting coalition aircraft more loitering time over Yemen, and permitting some coalition members to home base aircraft rather than relocate them to Saudi Arabia.