Facebook says any return to China would preserve free expression

Facebook Inc. said if it ever returns to China, the company will do it in a way that preserves rights to free expression and privacy -- issues that make such a move almost impossible today.

The social-media giant made the comments in a written response to questions from U.S. senators. Facebook's stance is more cautious than Google, which is trying to get its search engine back into China. That project has sparked harsh criticism and debate from employees and outsiders, who say the company is violating its mission. Google's leader, Sundar Pichai, has said the Chinese market is too big to ignore.

Since 2013, Facebook said it has been a member of the Global Network Initiative, a digital rights organization that adheres to United Nations' principles on businesses and human rights. The company is assessed on how well it adheres to the goals every two years.

"In keeping with these commitments, rigorous human rights due diligence and careful consideration of free expression and privacy implications would constitute important components of any decision on entering China," the company told U.S. senators. "Facebook has been blocked in China since 2009, and no decisions have been made around the conditions under which any possible future service might be offered in China.' ALSO READ: Facebook plans innovation hub in China despite tightening censorship

That doesn't mean the company stays out of the Chinese market completely. It has salespeople based there to sell ads to local companies that want to reach people outside of China. The company has also at times tried to open an office in Beijing, and once launched a photo-sharing app in the country called Colorful Balloons.

The company answered the questions as a follow-up to Chief Operating Officer Sheryl Sandberg's congressional testimony in September.