The employees are demanding more transparency so they can understand the moral implications of their work, said the Times, which obtained a copy of the letter.
According to the report, the secretive project, codenamed Dragonfly, led to a protest by 1,000 Google employees who objected to the company's efforts at supporting the restrictive, state-sponsored censorship.
"That the decision to build Dragonfly was made in secret, and progressed even with the AI Principles [to govern Google's ethical use of AI] in place makes clear that the Principles alone are not enough".
The multinational tech company withdrew its search engine from China eight years ago due to censorship and hacking.
Chief Executive Sundar Pichai told staff that though development is in an early stage, providing more services in the world's most populous country fits with Google's global mission. Pinchai responded by speaking at a weekly meeting at Google's California headquarters, where he said that Google was "not close to launching a search product in China", as per CNet.
When tweets from a New York Times reporter indicated that someone was providing her with the internal discussion, many within the company appeared to react with anger, according to sources.
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Both fell shortly after the break, however, with Ishant Sharma once again removing Cook, who edged behind to wicketkeeper Pant. Root held his ground, not convinced that the catch had been a clean one, while Marais Erasmus referred the matter upstairs.
Google declined to confirm the authenticity of the letter or comment on the town hall meeting. Undersigned Googlers expect future projects to have an ethics review structure that includes rank and file employee representatives; an ombudspeople; a clear plan to enable Googlers an individual ethical choice; and an ethical assessment of Dragonfly, among other projects.
The project, known internally as Dragonfly, was developed largely in secret, prompting outrage among employees who anxious they had been unwittingly working on technology that would help China withhold information from its citizens.
Note: A Code Yellow is a standardized process in Engineering for addressing new or long-simmering business-critical problems that span multiple groups.
Many Google employees were shocked to learn that one of their own was leaking real-time information to reporters during a company all-hands meeting on Thursday.
The first two questions from staff members at Google's Thursday meeting were about Dragonfly, the people said.
Project Dragonfly was accelerated following Google CEO Sundar Pichai's meeting with a top Chinese government official.