WASHINGTON—Obama administration officials are raising alarms about a scientific-cooperation pact between North Korea and Iran that officials said could advance the nuclear and missile programs of both countries.

The agreement, reached in September, bears a close resemblance to one North Korea signed with Syria in 2002, U.S. and United Nations officials said, just as Pyongyang began secretly constructing a plutonium-producing nuclear reactor in eastern Syria. "They have pretty much the same wording," said Olli Heinonen,...