Opposition parties called on ministers to ban arms sales to Saudi Arabia, with the SNP demanding Theresa May raise the plight of imprisoned dissidents in meetings with Mohammed bin Salman.
The Crown Prince had lunch with the Queen at Buckingham Palace. MPs joined a protest against the visit outside Downing Street on Wednesday afternoon.
At Prime Minister’s Questions, Mr Corbyn said British military personnel were “directing” Saudi military operations responsible for large-scale civilian casualties in Yemen.
But the Prime Minister strongly defended the UK’s “historic” ties with the Saudis, saying they had “saved the lives of potentially hundreds of people in this country” in a reference to UK-Saudi counter-terror co-operation.
A spokesman for the Labour leader said he was referring to the presence of British personnel advising the Saudi air force on targeting Houthi rebels. He said that if their role was to prevent collateral damage as claimed, they had been a “disastrous failure”.
Mr Corbyn said a “humanitarian disaster” was taking place in Yemen as a result of the bombing campaign and a Saudi blockade of Yemeni ports.
“Germany has suspended arms sales to Saudi Arabia but British arms sales have sharply increased and British military advisers are directing the war,” he said. “It cannot be right that her Government is colluding in what the United Nations says is evidence of war crimes.”
At PMQs, the SNP MP Stewart McDonald raised the case of Raif Badawi, a blogger arrested in 2012 and sentenced to 10 years in prison and 1000 lashes for “insulting Islam through electronic channels”.
Mr McDonald called on the Prime Minister to “stand at the Dispatch Box and say that Raif Badawi is no criminal, and that he should be set free”.
In urgent questions later, the Liberal Democrat leader Sir Vince Cable said there was “widespread concern” that “the dictatorial head of a medieval theocratic regime is being given the red carpet equivalent of a state visit”.