UPDATE 3-Saudi minister gives Trump message from crown prince, meets UK defence minister

U.S. President Donald Trump said on Tuesday he met Saudi Arabia's vice defense minister to discuss trade, oil prices and stability in the Middle East amid heightened tensions with Iran.

Prince Khalid bin Salman said on Twitter he had delivered a message from Crown Prince Mohammed bin Salman, the kingdom's de facto leader, during his meeting with Trump on Monday, without providing details. The White House confirmed the meeting took place after the Saudis tweeted a photo of the session, which took place in the Oval Office.

"Had a very good meeting with @kbsalsaud of Saudi Arabia. We discussed Trade, Military, Oil Prices, Security, and Stability in the Middle East!" Trump said in a tweet. Prince Khalid, a son of King Salman, also met the U.S. secretaries of defense and state on a trip scheduled after the killing of a top Iranian military commander in a U.S. strike in Iraq.

Later on Tuesday, he said he met in London with British Defense Secretary Ben Wallace and David Quarrey, the prime minister's international affairs adviser and deputy national security adviser, to discuss "regional and international efforts in the war against terrorism". Washington and London are key Western allies and arms suppliers for Riyadh, which is locked in a struggle with Tehran over regional supremacy.