Corbyn slams May over meeting with 'war ally' Mohammed bin Salman

May met the powerful young prince, described by Corbyn as her "war ally", at the G20 summit in Japan on Saturday.

The prime minister said she used the opportunity to urge the crown prince to pursue a solution to the conflict in Yemen via the United Nations. May also said she called for an "open and transparent" probe into the murder of Washington Post columnist Jamal Khashoggi.

Labour leader Corbyn, however, said the premier had fallen short of properly holding the de-facto Saudi leader to task, highlighting the UK's arms sales to Saudi Arabia.

"She should confirm the UK government will immediately stop selling arms to his regime and hold him to account over the horrific murder of the journalist Jamal Khashoggi," Corbyn said.

He also highlighted a recent decision by the UK court of appeal, which ruled that British arms sales to the kingdom are unlawful. The UK government is currently appealing the decision.

"The Court of Appeal has found the UK government 'made no attempt' to conclude whether the Saudi-led coalition had committed violations of international humanitarian law in the Yemen. 

"It is simply not good enough for Theresa May and her government to take the Saudis at their word".

Bin Salman, also known as MbS, became the focus of international scrutiny following the murder of Khashoggi at the Saudi consulate in Istanbul in October.

Khashoggi's body was dismembered by his killers and disposed of.

A recent UN report said there is "credible evidence" linking Saudi Crown Prince Mohammed bin Salman to the killing.

Riyadh, however has continued to insist that the murder was committed by rogue operatives acting on their own accord.

Bin Salman has also come under scrutiny for his continued pursuit of war in Yemen, where more than 91,000 have died over the course of the ongoing conflict.

The situation in Yemen has been described by the United Nations as the world's worst humanitarian crisis.