Story highlights Trump was apparently referring to a review of US nuclear weapons that began earlier this year

It is unclear to what extent, if any, the US nuclear arsenal has been modernized since Trump took office

Bridgewater, New Jersey (CNN) A day after an incendiary rebuke of North Korea, President Donald Trump touted US nuclear capabilities on Twitter, potentially escalating further the growing standoff with Pyongyang.

"My first order as President was to renovate and modernize our nuclear arsenal. It is now far stronger and more powerful than ever before," Trump wrote just before 8 a.m. ET from his golf resort here. "Hopefully we will never have to use this power, but there will never be a time that we are not the most powerful nation in the world!"

Trump was apparently referring to a review of US nuclear weapons that began earlier this year, which he directed Defense Secretary James Mattis to undertake in a presidential memorandum signed during a January visit to the Pentagon.

Such reviews of the US nuclear posture are required by Congress and typically occur every eight years. The Pentagon last conducted a review in 2010 that was ordered by then-President Barack Obama.

It is unclear to what extent, if any, the US nuclear arsenal has been modernized since Trump took office. Such efforts would require billions of dollars allocated by Congress, and Trump's administration has proposed increasing spending on nuclear programs by 11%, more than the overall increase to the defense budget.

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