Treasury Secretary Steven Mnuchin said on Sunday there was a risk of a trade war between the United States and China after the countries proposed imposing tariffs on billions of dollars' worth of one another's goods, but that he did not expect one.

"Our expectation is that we don't think there will be a trade war; our objective is to continue to have discussions with China ... I don't expect there will be a trade war - it could be, but I don't expect it at all," he told CBS' Face The Nation.

Mnuchin added that President Donald Trump and Chinese president Xi Jinping have a "very close relationship" and that the United States and China would continue to discuss trade issues.