Mohammed bin Salman will receive the red-carpet treatment when he arrives in the UK on Wednesday for a three-day visit, including lunch with the Queen at Buckingham Palace and dinner with the Prince of Wales and the Duke of Cambridge, as well as talks with senior ministers and national security officials.
Prince Salman's visit is expected to trigger large-scale demonstrations over Saudi Arabia's human rights record and its role in the bloody conflict in Yemen, where it has backed a coalition of forces against Houthi rebels in a three-year civil war that has descended into a humanitarian crisis.
Ms May has been urged to halt arms sales to the Middle Eastern kingdom until it ends its intervention in Yemen, as Government data shows Britain has licensed £4.6m worth of arms sales to Saudi Arabia since 2015, according to the Campaign against the Arms Trade (CAAT). However the Government insists it has "one of the most robust arms export control regimes in the world".
Ms May will outline Britain's "deep concerns" over the humanitarian crisis in Yemen during her meetings with Prince Salman, who she will host for dinner at Chequers on Thursday.
The Prime Minister's official spokesman said: "You can expect them to discuss Yemen and the Prime Minister to raise our deep concerns at the humanitarian situation. She will acknowledge the steps taken recently by Saudi Arabia to address the crisis but stress the importance of full and unfettered humanitarian and commercial access, including in the ports of Hodeidah and Salif.
"She will also reiterate how seriously we take allegations of violations against international humanitarian law and emphasise the need to ensure that these are investigated swiftly and thoroughly.
"She will make clear that we urgently need to see progress on the political track, which is ultimately the only way to end the conflict and humanitarian suffering in Yemen."
The powerful heir to the throne has been credited with ushering in social and economic reforms in Saudi Arabia, including ending the ban on women drivers, and the Government is keen to boost trade links with the oil-rich kingdom after Brexit.
The potential listing of Saudi energy giant Aramco on the London stock exchange next year could also feature in talks.
Labour reiterated its manifesto pledge to immediately suspend any further arms sales to the kingdom until a "comprehensive, independent, UN-led investigation into alleged violations of international humanitarian law in Yemen” is concluded.
Jeremy Corbyn told The Independent: “Theresa May should use this visit to announce the UK will no longer supply arms to Saudi Arabia while the devastating Saudi-led bombing of Yemen continues and make clear Britain’s strong opposition to widespread human and civil rights abuses in Saudi Arabia.”
Andrew Smith, from CAAT, said: “The Crown Prince should never have been invited to Downing Street: he leads a regime with an appalling human rights record and has overseen the destruction in Yemen.
“The UK has armed and supported the terrible war since day one, and there is no doubt that arms sales will be top of the agenda next week. Theresa May is putting the interests of arms dealers above the rights of Yemeni people.”
Kate Allen, UK director for Amnesty International, also urged the Prime Minister to use the visit as an opportunity to “finally show some backbone” when it comes to Saudi Arabia.
She said: “Time and time again, UK ministers have turned a blind eye to Saudi Arabia’s atrocious human rights record – barely mentioning the country’s crackdown on peaceful opposition figures, or the alarming prevalence of torture, unfair trails and grisly executions.
“Ahead of Mohammad bin Salman’s visit, Theresa May must finally do the right thing over UK arms sales – suspending all arms exports to Saudi Arabia while there’s any risk they’ll be used by the Saudi-led coalition to bomb civilians or enforce the crippling blockade in Yemen.”
The Saudi foreign minister said opposition to the Prince's visit to the UK was based on a “misunderstanding” of the war in Yemen.
Speaking to BBC Radio 4’s 'Today' programme on Tuesday, Foreign Minister Adel al-Jubeir insisted that the Saudi presence in Yemen was justified and said the war had been imposed on them by the Houthis.
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