Facebook founder Mark Zuckerberg surprised students in Beijing by conducting a question and answer session in Mandarin.He charmed the Chinese and international students by kicking off the half-hour session at Tsinghua University with the words “hello everyone” in Chinese.

A video of the event posted online showed the crowd cheering and applauding the 30-year-old entrepreneur’s heavily accented answers.

When asked about Facebook’s plans in the country – which currently bans access to the site – he said: “We’re already in China.

“We help Chinese companies increase their overseas customers, they use Facebook advertising to find more customers.

“So, we want to help different places in the world connect with China.”

Facebook has been inaccessible in mainland China since 2009, blacklisted by the ruling communist party along with Twitter, YouTube and Instagram.

However Chinese state news organisations and government bodies typically have social media accounts, and Facebook officials have made frequent trips to Beijing to meet business and government leaders.

Facebook has an office in Hong Kong, where the website is not blocked, and has also reportedly rented office space in Beijing in a bid to boost its business selling online adverts.

Mr Zuckerberg also discussed topics including his philosophy on founding a company and his view of Chinese innovation.

Asked by the moderator what he believes is the secret to Facebook’s success, Mr Zuckerberg said: “The most important thing is you can’t give up.

“It’s very difficult to develop a company. Most things won’t go smoothly. You’ll have to make some difficult decisions. You may have to lay some people off.

“If you don’t believe in your mission, it’s very easy to give up. Most founders give up. But the best ones don’t.”

He also said he wanted to challenge himself to learn Chinese: “I want to study Chinese culture. Studying the language helps me study the culture. So, I’m trying to learn the language. Also, I like a challenge.”

Reaction to his speech was mixed on permitted social media site Weibo.

One user said: “The only sentence that you should learn is, please unblock Facebook.”

While another asked: “I wonder how he can get on Facebook, when he’s in China?”

Some people praised him for his Chinese, but others mocked his pronunciation.

One said: “Somehow I think if he speaks in English, I would understand him better. Is there any video with Chinese subtitles?”