WASHINGTON (AP) - The Latest on North Korea's nuclear and missile programs (all times local):

6:20 p.m.

Republican Sen. John McCain says "great leaders" don't threaten foes unless they're ready to act - and he's not certain President Donald Trump is ready to act against North Korea.

McCain, who heads the Armed Services Committee, made the comments Tuesday in an interview on KTAR News in Phoenix.

He is responding to Trump's warning that North Korea could face "fire and fury" if it threatens the United States after a new report said U.S. intelligence officials believe Pyongyang has successfully produced a nuclear warhead that can fit inside its missiles.

McCain says he takes exception to Trump's comments "because you got to be sure you can do what you say you're going to do."

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3:30 p.m.

President Donald Trump says that North Korea "had best not make any more threats to the United States" or "they will be met with fire and fury like the world has never seen."

Trump issued the warning during a briefing on opioid addiction at his golf course in Bedminster, New Jersey.

A Japanese defense paper and a U.S. media report said Tuesday that North Korea may have successfully produced a miniaturized nuclear warhead that can fit inside its missiles.

That's a key benchmark in the country's attempt to become a full-fledged nuclear power.

Washington's alarm over North Korean leader Kim Jong Un's pursuit of a nuclear capability has intensified in the past month after the North conducted two tests of intercontinental ballistic missiles last month.

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1:29 p.m.

The Washington Post is reporting that U.S. intelligence officials assess that North Korea has successfully produced a miniaturized nuclear warhead that can fit inside its missiles.

That would mean North Korea has passed a crucial threshold on the path to becoming a full-fledged nuclear power.

The Post story, citing unnamed U.S. intelligence officials, said the confidential analysis was completed last month by the U.S. Defense Intelligence Agency.

Officials at the agency would not comment Tuesday. The Office of the Director of National Intelligence could not immediately be reached for comment.

Separately, Japan's defense ministry assessed in a report Tuesday that it is possible that North Korea has achieved the miniaturization of nuclear weapons and has developed nuclear warheads.

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