Senior White House Official Said to Figure in FBI ProbeThe Washington Post is quoting unidentified sources that report the FBI investigation into possible ties between President Donald Trump's political organization and Russia has identified a current senior White House official as “a significant person of interest” in the case. The senior official now under scrutiny is said to be someone close to the president, the newspaper said, attributing its report to “people familiar with the matter.” The senior official was not identified further, but the Post said the FBI probe was expected to intensify in the coming weeks. FBI agents assigned to the investigation are said to remain “keenly interested” in Trump aides who were influential during last year's political campaign but either did not join the new administration or have already left the government, such as former campaign chairman Paul Manafort and former national security adviser Michael Flynn. Watch: Trump Embarks on Foreign Trip Hoping to Leave Washington Turmoil Behind No media source currently available  Who's the subject? Current administration officials who have acknowledged contacts with Russian officials include Trump's son-in-law, Jared Kushner, and two of his Cabinet members, Attorney General Jeff Sessions and Secretary of State Rex Tillerson. The latest development in the Trump investigation was published Friday while the president was traveling to Saudi Arabia on the first leg of his first trip abroad as president — a series of diplomatic visits that the White House hopes will shift attention away from the political firestorm triggered by the dismissal last week of former FBI Director James Comey. Despite reports of a “significant person of interest” and an intensifying investigation, those watching developments closely in Washington say there is no indication yet that the filing of any criminal charges is imminent, or even likely. But the Post report does signal that the probe of the Trump team's involvement with Russia has reached the highest levels of the U.S. government.  Mueller could shift focus Earlier this week, Deputy Attorney General Rod Rosenstein named former FBI Director Robert Mueller as a special counsel to lead the government's investigation of Russian meddling in U.S. politics. The case began last July as an effort to determine whether any Trump associates coordinated their campaign activities with Russian operatives, but it has since broadened to consider whether any financial crimes were committed by people close to the president. It is unclear whether Mueller's leadership will affect the direction of the probe, but the Post said he is already bringing in new people to work on the team. A small group of lawmakers known as the Gang of Eight was notified of the change in tempo and focus in the investigation at a classified briefing Wednesday evening, the newspaper reported, again attributing its information to “people familiar with the matter.”