State Department offers buyouts as critics charge Trump administration with destroying diplomatic corps

— -- A State Department official confirms to ABC News that the department is offering "voluntary buyouts and early retirement incentives" as part of its effort to reduce its own ranks.

The Trump administration wants to get rid of 641 employees -- in addition to "normal attrition" -- by the end of 2018, in particular "to reduce unnecessary supervisory levels and organizational layering," the official said.

"The Department's goal is to meet its workforce reduction targets through the use of voluntary measures such as buyouts rather than involuntary measures, such as furloughs or ... layoffs," the official added.

The federal government's Office of Personnel Management and Office of Management and Budget both approved the buyouts -- which can reach a maximum of $25,000 before taxes, depending on the employee's level.

The agency has also frozen all new hiring and any promotions in an effort to limit the number of employees.

The news comes after a scathing letter from the Foreign Service union's president, questioning why the administration was depleting the diplomatic corps' ranks at a "dizzying speed" and raising red flags about "plummeting" interest in Foreign Service careers.

The State Department pushed back against that report, by ABC News and others, providing different numbers than the American Foreign Service Association -- even though both said they got their numbers from the State Department's Human Resources bureau. But Friday night's news is being taken as another sign that Secretary of State Rex Tillerson and the Trump administration are hollowing out the agency.

Richard Haass, the president of the Council on Foreign Relations and a close adviser to George W. Bush's Secretary of State, Colin Powell, tweeted a link to the New York Times, which first reported the buyouts, and said Tillerson's "focus on cutting staff, spending [is] misguided given need for diplomacy & Trump admin acute lack of experience."

Samantha Power, an adviser to former President Barack Obama and his ambassador to the United Nations, called tonight's news "inexcusable and, no matter how many times it is explained, inexplicable."

Dan Drezner, the Twitter-famous international relations professor and chief Tillerson critic, commented, "The only thing Rex Tillerson has been effective at as Secretary of State has been to eviscerate the State Department."