US President Donald Trump and Saudi Deputy Crown Prince and Defense Minister Mohammed bin Salman shake hands in the State Dining Room before lunch at the White House in Washington, DC, on March 14, 2017. Trump welcomed the prince to the Oval Office, as both countries expect to improve ties that were frequently strained under Barack Obama’s administration. Saudi Arabia is likely to welcome Trump’s harder line on its arch-rival Iran and there is likely to be less friction over Riyadh’s war against Iranian-backed Huthi rebels in Yemen.