WASHINGTON Saudi Arabias de facto ruler, Crown Prince Muhammed bin Salman, secretly spent $450.3 million on a Leonardo da Vinci painting last month, according to a Wall Street Journal report on Thursday based on U.S. government intelligence and an interview with a top Middle East figure in the art world.

The Journal noted that news of the princes purchase the highest ever in an art-world auction damages his claim that he will impose more transparency on the money accumulated by various members of the sprawling Saudi royal family. It suggests a huge amount of hidden wealth and, damningly for a man whose supporters paint him as a populist, excess.

Above all, it throws into stark relief the way the oil-rich monarchy continues to spend on luxuries while it pummels neighboring Yemen, the poorest country in the Arab world.

The New York Times corroborated the Journal story independently on Thursday. While the Saudi Embassy in Washington and the government of Abu Dhabi where the painting is to be displayed disputed that the crown prince was behind the purchase, and said a friend of his bought the piece on behalf of Abu Dhabi, the Financial Times later reported that the Saudi leadership bought the artwork as a gift for the Abu Dhabi government, a close regional partner.

The Yemen intervention is the chief product of the bond between Saudi Arabia and the United Arab Emirates. Pioneered by Mohammed in his capacity as defense minister, the U.S.-backed and Saudi-led campaign has now lasted more than two-and-a-half years and claimed thousands of civilian lives, many of them children , while causing the some of the worst starvation and disease crises in the world.

The Saudi-UAE coalition has caused significantly more pain there since Nov. 4, with the tightening of the blockade on the entry of shipments to Yemen. That action was taken in response to a missile strike over Riyadh launched by the Iranian-aligned Yemeni Houthi rebels theyre fighting, which Saudi officials say was a result of Iranian weapons transfers.

World leaders and humanitarian groups have urged the kingdom to ease the restrictions so food, fuel, medicine and other aid can get in so far to no avail. President Donald Trump , a vocal supporter of the Saudi leadership, joined the chorus on Wednesday with a surprise statement calling for complete aid access immediately.

The past months escalation has killed thousands and condemned thousands more to die in the near future, Oxfam America said in a statement Wednesday. Millions will die in a historic famine and public health crisis if President Trumps call is not heeded.

Given the unprecedented suffering in Yemen and the failure of countries involved like Saudi Arabia, the U.S., the U.A.E. and Iran to fully supply the close to 21 million people there who are in need the hundreds of millions of Saudi dollars spent on the painting could perhaps have been put to better use. Heres a few examples of the impact that money could have had:

• Every single one of those people in need could be fed for more than 5 weeks. (Oxfam told HuffPost it estimates that the cost of feeding one person in Yemen for one week is $4.)
• Every single family in need in Yemen could receive a sanitation kit that would help protect them from the huge outbreak of cholera, a vicious waterborne disease that was far less common before the outbreak of the war. (One kit to help a family costs $23, Oxfam said; around 3.5 million families are in need, so the total cost would be $80.5 million.)
• $450,000 spent over a year in a United Nations-managed project helped more than 12,800 people receive mattresses, blankets, gas stoves, buckets and emergency food rations. Those provisions could be supplied many times over.
• For the price of the painting and a yacht the prince bought last year, he could have filled the gap in the U.N.s emergency plan for Yemen, journalist Samuel Oakford noted on Twitter.

Saudi Arabia does fund significant relief for Yemen, and its officials note that it has accepted hundreds of Yemenis displaced by the fighting.

But experts say peace is nowhere in sight and that theres little sign of any serious talks to end the conflict between the Houthi rebels and the Saudi-backed international government.

In the meantime, as the Saudi-led campaign continues to drop bombs and block access to sea and airports, Yemens desperation continues to grow.

This story has been updated to include reactions from the governments of Saudi Arabia and Abu Dhabi, as well as additional reporting about the art purchase.