US President Donald Trump has talked up the advancements made in the US military under his administration, including missiles "four, five, six, and even seven times faster than an ordinary missile".
The American leader described the weapons as "super-fast missiles", suggesting the United States requires them because "Russia has some".
In a speech made to State Governors, Mr Trump praised the policy of "buying new" military arms, referring to a "tremendous $740 billion" budget for the military.
"We have the best equipment in the world," said the US President.
"The best missiles, planes, rockets. Everybody wants our equipment."
President Trump claimed his country has "no choice" but to spend on its nuclear programme, "because of what China is doing, what Russia is doing in particular".
“Russia and China both want to negotiate with us to stop this craziness of spending billions and billions of dollars on nuclear weapons," he said.
"The only way, until we have that [nuclear] agreement — the only thing I can do is create, by far, the strongest nuclear force anywhere in the world."
Last year, the US and Russia both withdrew from the Intermediate-Range Nuclear Forces (INF) treaty - an agreement signed by then-US President Ronald Reagan and then-Soviet leader Mikhail Gorbachev in 1987.
The 2021 US budget proposal, which was released on Monday, states "America’s nuclear deterrent is the backstop and foundation of the nation’s defense and that of America’s allies".
The document also says $3.2 million is available to continue the United States' hypersonic weapons development.
Cover image: Chris Kleponis/pool/PA.