United States President Donald Trump on Saturday said his Chief of Staff John Kelly would leave his job at the White House by the end of this year in a series of reshuffles keeping in mind the 2020 reelection campaign, AP reported.

“John Kelly will be leaving... I don’t know if I can say ‘retiring’. But, he’s a great guy,” Trump told reporters at the White House. “John Kelly will be leaving at the end of the year.”

Trump said he would announce Kelly’s replacement over the next day or two. An unidentified White House official said that Vice President Mike Pence’s Chief of Staff Nick Ayers is Trump’s top choice to replace Kelly, and the two have held discussions for months about the job.

The 68-year-old Kelly, a former Marine Corps four-star general, was secretary of Homeland Security in his first seven months of the Trump administration. He was appointed chief of staff on July 31, 2017, after Trump fired Reince Priebus who was accused of allegedly leaking information on the president’s personal life to mediapersons.

United States House of Representatives Speaker Paul Ryan lauded Kelly’s service and said the country was “better for his duty at the White House”. He praised Kelly as “a force for order, clarity and good sense”.

Earlier on Saturday, Trump nominated General Mark Milley as his next chairman of the joint chiefs of staff, the country’s top military adviser. If his nomination is confirmed by the Senate, Milley will replace General Joe Dunford who is scheduled to retire next summer.

Trump described Milley, currently the Army chief of staff, as a “great gentleman and a great patriot”.

Amid other diplomatic reshuffles, Trump on Friday had nominated State Department spokesperson Heather Nauert as the country’s next ambassador to the United Nations, replacing Nikki Haley who will leave the post by the end of the year. The president had also nominated conservative lawyer William Barr as his new attorney general.