Following US President-elect Donald Trump's telephone conversation with Taiwan President Tsai Ing-wen on Friday (2 December), China has said Trump and his transition team are "very clear" about China's "solemn position" on Taiwan.

China reacted angrily to the unusual conversation and lodged a diplomatic protest with the US, but the White House played down the issue.

China's foreign ministry spokesman Lu Kang said on Monday (5 December): "The Chinese side in Beijing and Washington lodged solemn representations with the relevant side in the US. The world is very clear on China's solemn position. The US side, including President-elect Trump's team, is very clear about China's solemn position on this issue," Reuters cited Lu as saying.

China woke up to critical tweets from Trump on Monday in which he took a dig at Beijing's economic policy and its military expansion in the South China Sea.

When asked who China lodged its protest with, Lu said: "I think it's easy to understand 'the relevant side'. In fact, China has maintained contacts and communication with the team of President-elect Trump."

Although China would not speculate on what prompted Trump to hold a telephonic conversation with Tsai, it is a sensitive matter raising serious concern in US-China relations, he added.

Lu did not directly comment on Trump's tweets, but defended the ties between China and the US. "The China-US economic and trade relationship has over many years always been a highly mutually beneficial one, otherwise it couldn't have developed the way it has today. China and the United States [are] maintaining good relations, a steadily developing relationship, and accords with the joint interests of both people."

Trump also received criticism from the Chinese media which called him "inexperienced". The newspapers suggested punishing the Taiwan government to send a message to Trump.

Donald Trump
China says it is maintaining contacts with the transition team of US President-elect Donald Trump Win McNamee/Getty Images