The heat waves in northern China are expected to abate by Monday before regaining strengthen later in the week.

China has a four-tier weather warning system, with red the most severe, followed by orange, yellow and blue.

Deadly fires are common in China due to weak safety standards and lax enforcement.

The concentration of fine particulates in the air in Beijing is currently 46.2 times the World Health Organization's annual air quality guideline value.

Iranian Foreign Minister Hossein Amir-Abdollahian and his Saudi counterpart Prince Faisal bin Farhan discussed steps towards reopening the embassies and consulates of the two countries, reports say.

This is in line with national trends, with China's population falling last year for the first time in six decades, weighed down by rising living costs, weak economic growth, and changing attitudes towards raising a family.

More than 28,000 new infections were reported nationwide with Guangdong province and the city of Chongqing logging over 16,000 and 6,300 cases respectively, health authorities say.

Beijing authorities are on high alert in the hope of preventing the numerous Omicron variant outbreaks in other cities from spreading to the capital.

Beijing initially denied the existence of any detention camps, but then later admitted it had set up 'vocational training centres' necessary to curb what it said was terrorism, separatism and religious radicalism in Xinjiang.

Beijing rejects the allegations, claiming to be fighting terrorism and ensuring the region's development.

Beijing, which has some of China's strictest Covid barriers for entry, has seen the number of infections rise after the national Golden Week holidays at the start of this month.

China claims nearly all of the South China Sea, a move labelled as 'expansive and unlawful' by the State Department's deputy assistant secretary for East Asia.