President Barack Obama on Tuesday will nominate Marine Gen. Joseph Dunford as the next chairman of the Joint Chiefs of Staff, U.S. officials said on Monday, in a widely expected pick likely to win swift Senate confirmation.

Dunford, commandant of the Marine Corps, would replace Army Gen. Martin Dempsey, who is expected to step down in September as the top military officer after a tumultuous four-year period that saw most U.S. forces withdraw from Afghanistan but thousands return to Iraq.

Dunford has experience in both wars, and before becoming the top Marine general in late 2014, led U.S. and international forces in Afghanistan as they handed over greater responsibility to Afghan troops battling a still-resilient Taliban.