China has already vowed to respond with any 'necessary measures'
Donald Trump has approved 25% tariffs on $50 billion worth of goods from China.
The US President said the move was aimed at preventing "unfair transfers of American technology and intellectual property to China".
He also claimed Chinese certain trade practices harm American economic and national security.
1,102 imported products - predominantly a range of machines and industrial products - will be impacted by the tariffs.
In a statement, President Trump said: "My great friendship with President Xi of China and our country’s relationship with China are both very important to me.
"Trade between our nations, however, has been very unfair, for a very long time. This situation is no longer sustainable."
He added: "[These tariffs] will serve as an initial step toward bringing balance to the trade relationship between the United States and China."
Ahead of today's announcement, China had already vowed to retaliate to any new US tariffs.
In a statement quoted by the South China Morning Post, a Chinese foreign ministry spokesperson said: "We want to reiterate that, if the US takes unilateral and protectionist actions which hurt China’s interests we will lose no time to respond and to take necessary measures to defend our own rights."
In April, the US announced a list of planned tariffs against China, prompting immediate fears of a trade war.
However, US officials later said the tariffs were put 'on hold' as negotiations continued with China.
Today's announcement comes amid the increasing tension between the the Trump administration and its allies - including Mexico, Canada and the EU - over the recently imposed US tariffs on steel and aluminum imports.