Washington, Jun 15 (IANS): US President Donald Trump has given his approval for his administration to put tariffs on $50 billion of Chinese exports, a media report said.

An official announcement is expected on Friday, an informed source told CNN on Thursday.

Trump's approval came after a meeting on Thursday with top economic officials, including Treasury Secretary Steven Mnuchin, Commerce Secretary Wilbur Ross and US Trade Representative Robert Lighthizer, the source added.

The move represents a serious escalation of trade tensions between the world's two largest economies - just as Trump has also picked fights with allies Canada, Mexico and the European Union over steel and aluminium.

In response to the development, Chinese Foreign Ministry spokesman Geng Shuang reiterated that Beijing would not honour its pledge to increase purchases of US goods if tariffs were imposed.

Beijing previously said it would respond to American tariffs on $50 billion worth of Chinese exports with retaliatory tariffs on $50 billion of US products such as cars, planes and soybeans.

For months, Trump has slow-walked threats of tariffs against China as punishment for intellectual property theft.

He first announced that the US would impose trade penalties on about $50 billion of Chinese goods in March.

After China warned it would retaliate, Trump threatened tariffs on a further $100 billion of Chinese products.

In mid-May, both sides announced a ceasefire after two rounds of trade negotiations, CNN reported.

The countries said in a joint statement that China would "significantly increase" purchases of US agricultural and energy products to reduce the trade imbalance, a top Trump administration demand.

Mnuchin subsequently declared the trade war "on hold".

Ten days later, the White House abruptly said it would proceed with the tariffs, along with new limits on Chinese investments in the US.

A further round of trade talks in Beijing earlier this month failed to yield any breakthroughs.