National Security Adviser Gen James Jones is retiring and will be replaced by his deputy, Tom Donilon. President Barack Obama is to announce the high-level staff changes at the White House on Friday. Gen Jones's announcement had been widely expected as Mr Obama nears two years in the White House. It follows news of the departure of several other senior White House advisers, including political staff and top economic adviser Larry Summers. Gen Jones, a former Marine Corps general, is the first high-level member of Mr Obama's national security team to depart. In recent weeks, Mr Obama's Chief of Staff Rahm Emanuel left to run for mayor of Chicago and senior political adviser David Axelrod departed to begin planning the president's 2012 re-election bid. Mr Summers, Mr Obama's top economic adviser, announced last month he would leave at the end of the year to return to Harvard University. Staff departures are not unusual at this point in a president's term, nearly half-way through the four years. Gen Jones is seen as close to the president, while Mr Donilon, a veteran Democratic political hand and former chief of staff to Bill Clinton's Secretary of State Warren Christopher, is not seen as part of Mr Obama's inner circle, analysts say. Source: BBC