Updated

Diplomats say that Iran nuclear talks will likely be adjourned Friday and extended past the July 20 target date for a deal.

Both sides had been prepared to talk until Sunday, which had been informally set as the deadline for the negotiations. But two diplomats have told The Associated Press the meeting will probably wind down early, because significant differences won't be bridged by Sunday.

The diplomats demanded anonymity Wednesday because they aren't authorized to divulge confidential information.

The talks are meant to result in a deal that curbs Iran's atomic programs in exchange for an end to nuclear-related sanctions on the Islamic Republic.

U.S. Secretary of State John Kerry spoke of "very real gaps" Tuesday after meetings with Iranian Foreign Minister Mohammad Javad Zarif.