The UK provided 11 Typhoon jets and "substantial support" to Saudi Arabia in 2014, ahead of the Gulf state's controversial bombing campaign in Yemen in March, recent documents have revealed.

The British Ministry of Defense (MoD) has previously declined to discuss the exact nature of munitions provided to Saudi Arabia. But an obscure report published by the UK government's Department for Business Innovation and Skills has revealed the extent of training, support, and weaponry sold to the Gulf state.

The disclosures will renew concerns about the precise level of British involvement in Saudi Arabia's bombing campaign in Yemen, which has killed at least 1,693 civilians since March 26, according to the United Nations Office for Human Rights. Yemen is currently facing a humanitarian crisis exacerbated by the bombing campaign, which has the full backing of the UK government.

The MoD has repeatedly stated that it is not participating directly in the Saudi-led airstrikes; however, new disclosures reveal that British "liaison personnel" remain stationed at the Saudi and coalition air and maritime headquarters.

The Typhoon fighter jets were delivered by UK arms manufacturer BAE Systems as part of a 72-aircraft deal worth 4.4 billion pounds ($6.8bn), first agreed in 2005, but finally settled in 2014. Foreign secretary Philip Hammond confirmed in March that British-built aircraft are being used in the military campaign.

The details were revealed in the UK's Strategic Export Controls Annual Report, published on Thursday July 16. The document outlines weaponry, associated training, and support that has been provided to the Gulf State.

Provisions under the UK's "longstanding Government-to-Government defense cooperation program" include Typhoon, Tornado, and Hawk aircraft, mine countermeasure vessels, associated munitions, infrastructure, logistics, and manpower support packages.

In addition, throughout 2014 the UK continued to provide "substantial support" for equipment already in service, as well as training for new aircraft and their systems.

The document also reveals that the UK sold an undisclosed quantity of "aircraft spares" to the Gulf state as "disposals" — surplus military equipment typically available at a discount.

Concerns have been raised in UK Parliament's House of Lords about the level of input provided by British military personnel.

Earlier this month the Marquess of Lothian submitted a written question to the House of Lords questioning the extent of UK support of Saudi Arabia's military campaign in Yemen.

"We are not participating directly in Saudi-led military operations in Yemen," Earl Howe replied. "But we are providing technical support, precision-guided weapons and exchanging information with the Saudi Arabian armed forces through pre-existing arrangements.

"In addition to the personnel who continue to provide support for equipment supplied, we have a small number of liaison personnel in Saudi and coalition air and maritime headquarters. This includes personnel in the Maritime Coalition Coordination Centre in the region supporting the delivery of humanitarian aid into Yemen."

Saudi Arabia deployed 100 fighter jets in March in an attempt to stem the advance of Houthi rebels, who are allegedly backed by Iran.

The strikes have failed to prevent the Houthis from gaining territory, although they have prevented them from seizing bigger sections of Yemen.

The Saudi-led coalition has also blockaded Yemen's air space and ports, cutting off supplies of food and fuel, and crippling water supplies which usually come from gas-powered pumps.

More than 20 million in Yemen now require humanitarian aid, according to aid agency UNICEF.

An MOD Spokesperson told VICE News: "The UK is not participating directly in Saudi Arabia's military operations. We are providing support to the Saudi forces through pre-existing arrangements, including a small number of personnel in Saudi and coalition headquarters and others working on routine projects. Any detail of Saudi Arabian operations is rightly a matter for them to comment on."

A Business, Innovation and Skills spokesperson told VICE News: "We are monitoring the situation in Yemen very closely.

"The UK aims to operate one of the most rigorous and transparent export control regimes in the world. Each license application is rigorously assessed using internationally recognized criteria. Export licenses will not be granted where there is a clear risk that the exports might be used for internal repression or in serious violation of international humanitarian law."

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