Twitter, which has its Europe Middle East and Africa (EMEA) headquarters in Dublin, is opening an office in Hong Kong to try to attract mainland Chinese advertisers, even though the social network has been blocked there since 2009.

The Chinese government believes that Twitter, along with Facebook and YouTube, threaten social order.

Twitter’s Hong Kong office will seek out mainland companies which want to advertise overseas, even though most of China’s online population of 649 million will be unable to view the ads.

"This is the first market we've gone into where we're targeting outside of the country," Peter Greenberger, Twitter's sales director for emerging markets, told the South China Morning Post. The main targets will be "big advertisers looking to reach overseas", Greenberger said.

Twitter made $479 million (€449 million) in fourth-quarter revenue from advertisers who paid to inject ads, known as “promoted tweets”, into users’ timelines. Twitter has 288 million users worldwide.

Even though Twitter is banned, state media such as the Xinhua news agency, the Global Times and the China Daily promote their Twitter feeds on their websites as they try to gain readers elsewhere.