WASHINGTON (Reuters) - U.S. Secretary of State Rex Tillerson last month tightened his control over the State Department by taking back powers previously held by the top career foreign service officer, an action critics said would delay major decisions and marginalize career diplomats.

U.S. Secretary of State Rex Tillerson testifies before the Senate Foreign Relations Committee on Capitol Hill in Washington, D.C., U.S., June 13, 2017. REUTERS/Aaron P. Bernstein

The move retracted broad decision-making authority granted to the agency’s third-highest ranking official, the undersecretary for political affairs, by former Secretary of State Hillary Clinton. Most of those powers will be reserved instead for Tillerson and his deputy.

Tillerson is broadly reviewing how authority is delegated, a State Department official said, which will “result in a streamlining of delegations, which will promote greater transparency, clarity and effectiveness in decision-making within the Department.”

On July 17, Tillerson reversed Clinton’s 2009 decision to empower the undersecretary for political affairs, currently career diplomat Thomas Shannon, with “all authorities and functions vested in the Secretary of State.”

Former officials said Clinton’s delegation of authority was helpful in allowing decisions to be made quickly when she or her deputy were traveling abroad.

“Everyone travels all of the time if you’re doing your job right as a diplomat,” said a former State Department official who served during the Obama administration and requested anonymity. “There has to be some delegation of authority, or the work simply doesn’t get done.”

Tillerson’s decision came as most of the high-level positions at the State Department are either empty or filled by career officials in an “acting” capacity. The secretary has said he wants to be cautious about hiring while he is conducting a review of the State Department’s organization.

On Tuesday, Tillerson acknowledged to reporters that “I have a lot of open slots,” but said he had been able to accomplish a great deal “because there are remarkable, talented professional foreign service officers in this building.”

But the slow pace of appointments has logjammed decision-making and resulted in a rank-and-file bureaucracy disconnected from top officials, diplomats and some members of Congress said.

“We don’t know what the policies are, and the diplomats don’t know what the policies are,” Senator Ben Cardin, the senior Democrat on the Senate Foreign Relations Committee, said on Tuesday.

‘POWER GRAB’

The second authority Tillerson took back from the undersecretary for political affairs in July was approval of State Department reports to Congress, which will now sit with the Office of Policy Planning, an internal State Department body usually headed by a political appointee. Unlike other senior officials, the office director and staff do not need Senate confirmation.

The State Department is required by law to produce hundreds of reports for Congress each year, including on acts of terrorism, human rights conditions in different countries, countries’ narcotics control strategies, the state of religious freedom around the world, and human trafficking.

Typically, such reports are prepared by offices and embassies with expertise in the relevant issue, and are reviewed by the State Department’s Bureau of Legislative Affairs and top aides to the secretary of state before being sent to Congress.

Three former officials said giving the policy planning staff final sign-off on the reports could inject political considerations into their preparation. The undersecretary for political affairs is typically a career foreign service officer, and oversees seven regional bureaus.

The move represents a “power grab” by the policy planning body, said Eliot Cohen, who served as State Department counselor during former President George W. Bush’s administration.

“You need a strong undersecretary for political affairs,” Cohen said. “You can’t run the State Department with a tiny office ... you need to go out and establish good working relationships with the professionals of the department.”