Mr Priebus' 189-day tenure was the shortest in modern history for a White House chief of staff.
In 2004, Kelly came back from a two-year command position in Iraq and served as the legislative liaison for the Marines until 2007, before retiring in 2015 from the military.
Firing Sessions or special counsel Robert Mueller - a move that has reportedly been considered by Trump and that would effectively end the Russian Federation probe that has been vexing him - could be one step too far even for this president. "He is a Great American".
Trump has picked Homeland Security Secretary John Kelly as his new chief of staff.
Mark Corallo, spokesman for the President's legal team, resigned amid reports of disagreements in dealing with the inquiry into claims of Russian meddling in last year's U.S. election and possible collusion with the Trump campaign. In an interview with conservative TV channel Fox News, she talked about him having somewhat of a hard time and said: "Somebody is trying to get in his way and scare him off". Priebus was already serving as chairman of the Republican National Committee and saw an opportunity to make the real estate mogul a high-dollar supporter of the party.
Even so, Trump brought on Priebus as White House chief of staff - a chief aide who essentially serves as the president's right-hand man for running the government. Those questions sharply escalated this week with the arrival of Scaramucci, the hard-charging communications director who was hired over Priebus' objections.
Manchester United v Real Madrid: International Champions Cup
To be fair to the slick-haired goalkeeper, he never openly stated his desire to leave the club as many footballers do. United have been trying to sign Ivan Perisic from Inter Milan and reportedly want to add Nemanja Matic from Chelsea .
In April, Kelly bluntly challenged members of Congress critical of the Trump administration's aggressive approach to immigration enforcement to either change the laws or "shut up". On health care, immigration, foreign policy, trade, and so many other issues, the White House has devolved into hostile camps led by various chieftains like family advisers Jared Kushner and Ivanka Trump, chief strategist Stephen K. Bannon, National Security Adviser H.R. McMaster, and chief economic adviser Gary Cohn. Trump had focused on him in recent days, telling those close to him that he believed military discipline was what his administration needed.
Priebus brought with Spicer, a former RNC official, with him to the White House.
Several days later, Mr Scaramucci tweeted that someone had illegally leaked financial information about him, conspicuously mentioning Mr Priebus's twitter handle.
Republican Sen. Lindsey Graham of SC, a frequent Trump critic, said that, as Homeland Security chief, Kelly has "been very effective in engaging members of Congress and communicating a coherent message for the President".
Kelly's Department of Homeland Security is responsible for enforcing border security and has taken a tough line on immigrants inside the United States.