RIYADH -- US President Donald Trump arrived in the Saudi capital Riyadh on Tuesday, kicking off his visit to the Middle East amid calls for Washington to play a role in facilitating regional stability.

The four-day whirlwind tour will take Trump to Saudi Arabia, Qatar, and the United Arab Emirates, where the US president intends to meet with Gulf leaders and finalize investment deals worth trillions of US dollars.

The visit comes amid ongoing turmoil in the Middle East: negotiations between the United States and Iran over nuclear issues have shown little progress; Israel's offensive in Gaza continues; and there are no clear signs of de-escalation in its hostilities with Yemen's Houthis and Lebanon.

The United States has come under widespread regional criticism for backing Israel's military escalation and proposing the relocation of Palestinians from Gaza. Regional analysts hope that Washington could play a meaningful role during Trump's visit by promoting a ceasefire and easing tensions.

With many issues in the Middle East "unsolved," the need for the United States to coordinate with regional countries appears to be "more pressing than ever," said Abdulaziz Sager, chairman of the Gulf Research Center.

Saudi Arabia marks Trump's first major official overseas visit of his second term. On his inauguration day in January, Trump said that he would choose Saudi Arabia as his first destination "if Saudi Arabia wanted to buy another 450, or 500 billion (dollars' worth of US products)."