Saudi Arabia’s Crown Prince Mohammed bin Salman was welcomed by Queen Elizabeth II — and criticized by protesters against the war in Yemen — as he began a three-day visit to Britain on Wednesday.

Britain is rolling out the red carpet for Saudi Arabia’s de facto ruler, who had lunch with the queen at Buckingham Palace and will dine later with Prince Charles and Prince William.

He is also due to meet with Prime Minister Theresa May, who said she would raise concerns about human rights during talks at 10 Downing St.

Critics say Britain has been slow to condemn rights abuses by Saudi Arabia, a key regional ally and major purchaser of U.K.-made weapons.

A Saudi-led coalition has been battling Iran-allied rebels in Yemen since 2015 in a war that has killed more than 10,000 people and driven the Arab world’s poorest country to the brink of famine. The kingdom faces wide international criticism for its airstrikes killing civilians and striking markets, hospitals and other civilian targets.

Campaigners against the war rallied near Parliament and said they would protest later outside the gates of Downing St.

Asked by Labour Party leader Jeremy Corbyn whether she would condemn Saudi Arabia’s “shocking abuse of human rights,” May defended Britain’s close ties with the authoritarian kingdom.

“The link that we have with Saudi Arabia is historic, it is an important one and it has saved the lives of potentially hundreds of people in this country,” May said in the House of Commons.

“We’re all concerned about the appalling humanitarian situation in Yemen,” May said, adding: “I will be raising concerns about human rights when I meet him.”

Modernization measures

The crown prince has shaken up his deeply conservative country since he became heir apparent to King Salman last year.

The 32-year-old royal swiftly consolidated power by sidelining rivals and stepped up Saudi Arabia’s rivalry with Iran. He has also has pushed through a number of dramatic social reforms, including allowing women to drive and lifting a ban on movie theaters.

Critics say the modernization measures mask continuing rights abuses. Human rights charity Reprieve says the number of executions in Saudi Arabia has doubled since the crown prince took charge.

The three-day visit is also due to include lunch with May on Thursday at the prime minister’s rural retreat, Chequers, and talks with Defense Secretary Gavin Williamson.