The number of employees due to return to work was not immediately clear.

Virgin Orbit chief executive Dan Hart announced the partial resumption in an email to employees Friday night, said the three people, who requested anonymity to discuss internal company matters.

Discussions over Virgin Orbit's investment plan to stave off bankruptcy were ongoing, one of the sources said.

Virgin Orbit said in a statement that it was targeting an "incremental resumption" of operations to support its next launch.

"Our first step will begin Thursday of this week, when we plan to return a subset of our team to focus on critical areas for our next mission," the company said.

(Reporting by Joey Roulette; Editing by Jacqueline Wong and Jamie Freed)