Donald Trump vows to expand US nuclear arsenal to be 'top of pack'

US President Donald Trump has said he wants to expand the nation's nuclear capacity to ensure it is at the "top of the pack".

Mr Trump claimed the US has fallen behind in its atomic weapons capacity.

President Trump will address his plans for defence and border security in a speech to Congress next week titled "The Renewal of the American Spirit."

White House press secretary Sean Spicer said Mr Trump will also discuss taking care of the nation's veterans and his plans for improving the nation's economy.

A Trident II, D-5 missile is seen being launched by the US Navy off the coast of Florida in 1989. Credit: AP

Mr Trump made the nuclear pledge in a Reuters interview in which he also confirmed he would complain to Russian President Vladimir Putin about Russia's deployment of a cruise missile in violation of an arms control treaty.

The president also called on China to exert more influence on North Korea.

Speaking from the Oval Office, Mr Trump said Beijing could solve the national security challenge posed by Pyongyang "very easily it they want to".

Mr Trump, who recently condemned North Korea's renewed ballistic missile tests, reiterated he was "very angry" at the North's actions.

He suggested the US might consider quickening a missile defence system for its allies Japan and South Korea in response.