Germany on Saturday discouraged non-essential trips to China, the world's most populous nation, which is struggling with a surge in Covid cases after relaxing strict virus restrictions.

"We currently discourage non-essential trips to China. The reason is a peak in Covid infections and an overwhelmed health system," the German foreign ministry said on Twitter.

More than a dozen countries have slapped fresh travel regulations on travellers from China.

European Union experts this week "strongly encouraged" the bloc's 27 member states to demand Covid tests from people on flights from China and conduct random tests on arrivals.

Several other EU nations -- including Germany, France, Germany, Italy and Spain --- have already announced Covid test requirements on travellers coming from the Asian nation.

The United States and Japan are among the non-European countries to have brought in similar measures.

Chinese authorities have said in recent days that the first wave of infections has hit a peak in cities including Beijing and Tianjin.

But the end is far from near, with officials warning of a multi-pronged outbreak in the coming weeks as city workers return to their rural hometowns during the winter travel season.

AFP