Mr. Bonderman later apologized to Ms. Huffington and Uber’s employees in an email, before resigning from the board a few hours later.

“I do not want my comments to create distraction as Uber works to build a culture of which we can be proud,” Mr. Bonderman said in a statement. “I need to hold myself to the same standards that we’re asking Uber to adopt. Therefore, I have decided to resign from Uber’s board of directors.”

Before the meeting, Mr. Kalanick said in an email to employees that he would take time off to work on himself and reflect on building a “world-class leadership team” for the company. He did not specify how long he would be away, and he did not appear at the staff meeting.

Uber did not release Mr. Holder’s full report. Instead, the company highlighted the changes it would make to fix its problems. The recommendations included limiting Mr. Kalanick’s responsibilities by reallocating some of his duties, and by giving a chief operating officer more responsibilities at the company. Mr. Holder also recommended that Uber appoint an independent chairman and create an oversight committee on the board. The goal is to bolster the checks and balances on management, according to the recommendations.