WASHINGTON — President Trump said on Thursday that he was preparing to officially declare the United States’ worsening epidemic of opioid overdoses as a national emergency, accepting an urgent recommendation from a national commission that he appointed.

“The opioid crisis is an emergency, and I’m saying officially right now it is an emergency,” Mr. Trump told reporters before a security briefing at his golf club in Bedminster, N.J. “It’s a national emergency.”

The president’s commission concluded last month that such a declaration was its “first and most urgent recommendation.” Led by Gov. Chris Christie of New Jersey, Mr. Trump’s one-time presidential rival, the commission said that such a declaration would help direct more resources and attention on the crisis plaguing communities across the country.

Mr. Trump’s top health care official had played down the likelihood of an emergency declaration. Tom Price, the secretary of health and human services, told reporters on Tuesday that the crisis “can be addressed without the declaration of an emergency, although all things are on the table for the president.”