President Obama plans to announce a Cabinet shuffle next week, asking San Antonio Mayor Julian Castro to take the reins at the Department of Housing and Urban Development and moving current Housing Secretary Shaun Donovan to the Office of Management and Budget as its next director, according to Democratic officials familiar with the proposed moves.

Both men have reportedly agreed to the plan, and the White House is expected make the nominations public in the coming days.

Castro, 39, is serving his third two-year term as mayor of the nation's seventh-largest city and earned national attention in 2012 when he gave the keynote address at the Democratic National Convention. Ever since, Castro has been considered one of a handful of Democrats who could serve as the party's vice presidential nominee in 2016, especially if Hillary Rodham Clinton wins the Democratic nomination for president.

The mayor has been undergoing vetting by the FBI for a possible Cabinet post, according to two government officials who were not authorized to discuss the process publicly. Castro had previously rejected offers from Obama join his Cabinet, but was approached again a few weeks ago about taking the HUD job.

White House spokesman Eric Schultz said Saturday that the there was no personnel announcement to make "at this time."

Donovan, the current HUD chief, has served as head of the nation's top housing agency since the start of the Obama administration. He has been rumored for years to be up for consideration for other government posts. Currently, the position of director of the Office of Management and Budget is expected to become vacant soon as Sylvia Mathews Burwell prepares to depart to become the new secretary of health and human services.

Castro's nomination could result in Obama adding a Hispanic appointee to a Cabinet that only lightly represents the nation's fastest-growing voter bloc. The White House has faced criticism in recent years for not appointing more minorities, especially Hispanics, to senior government jobs, especially since Latinos provided strong support for Obama in 2008 and 2012.

Castro's twin brother, Joaquin Castro, is a first-term Democratic congressman representing a San Antonio-area district.

Castro's hometown newspaper, the San Antonio Express-News, first reported the developments Saturday.

Juliet Eilperin contributed to this report.