Former White House National Security Council official Victor Cha says U.S. President Barack Obama has only approved a single round of high-level talks between U.S. special envoy Stephen Bosworth and North Korea.

Bosworth will head to North Korea on Tuesday for three days worth of talks with officials in Pyongyang.

Cha, the Georgetown University professor and current Korea Chair at the Center for Strategic and International Studies (CSIS), said Washington will decide after Bosworth's visit whether additional talks with Pyongyang are necessary.

Cha also said the U.S. will not allow Bosworth's trip to turn into a strict one-on-one contact excluding other members of the six-way nuclear dialogue.

He said that ideally the envoy's visit would spur an agreement on Pyongyang's return to the multilateral talks and its implementation of the September 2005 six-way agreement.

Cha said the worst-case scenario would involve North Korea requesting the cancellation of U.N. sanctions resolution 1874 and demanding a U.S. apology.