But one diplomat said Turkey had blocked approval over the wording of geographical locations, including with regard to Cyprus.
There was still an opportunity to find a solution before the NATO summit in mid-July in Vilnius, the diplomat added.
Turkey's diplomatic mission to NATO said it would be wrong to comment on a secret NATO document, adding only that "the usual process of consultations and evaluation among allies is continuing".
The so-called regional plans comprise thousands of pages of secret military plans that will detail how the alliance would respond to a Russian attack.
"While regional plans were not formally endorsed today, we anticipate these plans will be part of a series of deliverables for the Vilnius Summit in July," a senior U.S. official told Reuters.
Persons:
Jens Stoltenberg, Sabine Siebold, Andrew Gray, Charlotte Van Campenhout, Angus MacSwan
Organizations:
NATO, Vilnius Summit, Reuters, Thomson
Locations:
BRUSSELS, Turkey, Ukraine, Brussels, Cyprus, Vilnius, NATO, Afghanistan, Iraq, Soviet Russia, Moscow, U.S