WASHINGTON (AP) – President-elect Donald Trump is suggesting that the United States must “greatly strengthen and expand its nuclear capability.”

Trump tweeted Thursday that the U.S. must bolster its arsenal “until such time as the world comes to its senses regarding nukes.”

It was not immediately clear what Trump meant.

The tweet comes a day after Trump met with several military procurement officers to discuss defense budgets, including Lt. Gen. Jack Weinstein, the deputy chief of staff for strategic deterrence and nuclear integration for the Air Force.

During the campaign, Trump had suggested that the U.S. expand its arsenal and mused that the world would be “better off” if other countries, including Japan and South Korea, had nuclear capabilities.