United Kingdom Prime Minister, Theresa May, Wednesday, raised concerns about human rights in Saudi Arabia during talks with the country’s crown prince, Mohammed bin Salman.

Salman had begun a three-day UK visit amid protests against his country’s role in the war in Yemen, reports BBC.

The PM said ties with Saudi Arabia had saved hundreds of UK lives but she had urged full access for humanitarian aid in Yemen and a political solution.

However, Labour leader Jeremy Corbyn accused the government of “colluding” in war crimes by selling arms to Riyadh.

The 32-year-old crown prince, seen by some as a modernising force in the Gulf State, held talks with Mrs May and cabinet ministers at No 10 ahead of a summit at Chequers on Thursday.

He has already had lunch with the Queen and Duke of York, and is due to have dinner with the Prince of Wales and Duke of Cambridge.

The crown prince, who is regarded as being heir presumptive to the 82-year old King Salman, said there were “huge opportunities” to boost trade between the two countries while the UK and Saudi Arabia had to work together to deal with “failed states…terrorist and extremist organisations” in the Middle East.

The UK hopes to capitalise on Saudi plans to open up and diversify its economy by agreeing up to £65bn in mutual trade and investment opportunities over the next 10 years, as well as a significant role for the UK in advising on the modernisation of the Saudi schools system.

But there were some protesters outside Downing Street demonstrating against the killing of Yemeni civilians in air strikes by a Saudi-led multinational coalition – backed by the UK and US – that is battling the rebel Houthi movement.

Saudi Crown Prince, Mohammed bin Salman had a lunch earlier with Queen Elizabeth II

The crown prince is credited with kick-starting economic and social reforms in the conservative desert kingdom, such as the upcoming lifting of the ban on women driving.

In a statement following the talks, Downing Street said Mrs May had offered assistance to “progress and intensify these reforms, particularly on women’s rights, and on universal human rights”.

The prime minister expressed particular concern about the case of Raif Badawi, a Saudi blogger sentenced to 1,000 lashes and 10 years in prison for “insulting Islam” online.

Many have criticised the crown prince’s decisions to intervene in Yemen and impose a de facto blockade of neighbouring Qatar, as well as crack down on perceived opponents of his policies.