Washington (CNN) -- The United States and Iran are adding a new round of senior-level talks about the latter's nuclear program, discussions separate from the so-called P5+1 process continuing in Vienna.
The increase of diplomatic effort comes as an interim agreement reached between Iran and the five permanent members of the U.N. Security Council nears its end.
That deal eased some economic sanctions in return for Iran rolling back parts of its nuclear program, which the United States and others believe is designed to produce a weapon. Iran says its nuclear intentions are peaceful.
Major disagreements on a comprehensive agreement remain, a senior administration official told CNN on Saturday. The new talks appear to be a push to see whether roadblocks can be overcome.
"We believe we need to engage in as much active diplomacy as we can to test whether we can reach a diplomatic solution with Iran on its nuclear program," the official said. "These consultations come at an important juncture of the negotiations, and they will give us a timely opportunity to exchange views in the context of the next P5+1 round in Vienna."
The added talks are not a substitute for the P5+1 process, the official said. P5+1 consists of the United States, China, Russia, Britain, France and Germany.