Facebook has been banned in China since 2009, but CEO Mark Zuckerberg is determined to make inroads in the country with the world's largest Internet population. On Monday, Zuckerberg was appointed to the board of the prestigious Tsinghua University School of Economics and Management. And on Wednesday he did a 30-minute public Q&A entirely in Mandarin.

"We discussed connecting the world, Internet.org, innovation and the early days of Facebook," Zuckerberg wrote on his Facebook page.

With Zuckerberg's appointment to the university post, he joins execs from Western companies like Anheuser-Busch InBev, IBM and General Motors. Analysts see it as a key step to building the case for Facebook to re-enter China.

"This is just one more data point to me that confirms [that] the potential for Facebook entering China is likely to happen over the next couple of years," Victor Anthony, managing director and equity analyst at Topeka Capital Markets, told Bloomberg. "I don't know the exact timing but this is a matter of 'when,' not 'if.'"

The university board has strong ties to the Chinese central government. Reuters reported that it is an informal meeting ground for Chinese policymakers and those wishing to do business in China. Among other members of the board are Goldman Sachs CEO Lloyd Blankfein and Apple Inc. CEO Tim Cook.

"Tsinghua is an amazing center of learning and research, and it has been inspiring to me to be with so many talented future Chinese leaders," Zuckerberg wrote.

Zuckerberg, who is fond of annual challenges, vowed to learn Mandarin, in 2010. His wife, Priscilla Chan, was born in Massachusetts to Chinese immigrant parents.