Saudi Arabia's future king has hidden the whereabouts of his mother from his father and the public, according to U.S. officials.Crown Prince Mohammed bin Salman has given his father, King Salman, a number of different explanations for her absence, say 14 current and former U.S. officials who spoke to NBC on condition of anonymity. Among the fabrications he is said to have created is that she is receiving medical treatment abroad.Years of intelligence have led U.S. officials to believe that the Saudi heir, who is now 32, is concealing his mother's location. The officials say that the crown prince was motivated by a belief that she opposed his ascendancy to the throne and that she would use her position as King Salman's third wife to prevent it.One source close to the royal family told NBC that the prince was concerned that his mother was trying to "empower her siblings." That allegedly caused a rift between the prince and his mother years ago.Little information is publicly available about the mother-son relationship. Crown Prince Mohammed is her firstborn son, and according to Western diplomats who spoke to the New York Times in 2015, she "worked hard to promote him as his father's successor.""He is her eldest," a longtime associate told the publication. "For her, he is her glory at the end of the day."Officials first assessed that Princess Fahda bint Falah Al Hathleen, the crown prince's mother, was being hidden during the Obama administration. At a meeting at the White House in September 2015, King Salman reinforced that assessment when he told then-President Barack Obama that his wife was in New York receiving medical care. Obama did not notify him that the princess was not in New York, officials told NBC.They also said that in early 2016, the U.S. picked up communications in which the crown prince discussed his efforts to separate his mother from his father without the latter's knowledge.The crown prince's mother wouldn't be the first Saudi royal whose movements were restricted since the prince swept into power in June 2017. He unseated his cousin, then-Crown Prince Mohammed bin Nayef, who was confined to his Jiddah palace with guards loyal to the crown prince, reported the Wall Street Journal. In November, ministers and princes were arrested and placed under house arrest at the Ritz-Carlton in Riyadh.The Saudi Embassy in Washington denied to NBC the claims that the princess is separated from her husband or under house arrest.Officials said their assessment is based on human sources, intercepts and information gleaned from countries that shared with the United States.NBC's report comes at a time when the conservative country has taken steps to offer women more rights. The kingdom is lifting a ban on women driving, and for the first time women are also able to join the military. The crown prince's Vision 2030 for the country includes a goal of bringing more women into the workforce, "from 22% to 30%."King Salman, now 82, has said that he misses his wife. But by secretly keeping her out of sight, his son is showing a willingness to remove what he perceives as obstacles to his role as future king, current and former officials tell NBC.President Trump will host the crown prince at the White House on March 20. Copyright 2018 NPR. To see more, visit http://www.npr.org/.