US President Donald Trump has called for a 50 percent increase in US military spending to $1.5 trillion by 2027.

The US Congress approved a defense budget of $901 billion last December, and Trump has called for that figure to be more than doubled.

"This will not only build a great defense force, but will also allow us to be more secure, even when we have enemies," Trump said in a post on his social media account on Wednesday.

In related news, contractors working with the US military have threatened to reduce payments to their owners if they do not quickly deliver weapons and build manufacturing facilities.

After Trump made this announcement, the stock prices of the so-called giant arms manufacturers in the New York Stock Exchange rose.

Economists have warned that the gap between America's spending and its income is widening.

But the president said Washington could easily meet the $1.5 trillion budget requested, "thanks to the money I brought in through tariffs."

Since his first term in office, Trump has called for increased military spending by the United States and its allies.