North Korea has canceled for a second time its invitation for a senior U.S. envoy to visit the country to discuss a long-detained American's possible release, the State Department said Monday, according to AP. The cancellation comes only days after detained American missionary Kenneth Bae told a pro-Pyongyang newspaper that he expected to meet this month with the envoy. It signals an apparent protest of upcoming annual military drills between Washington and Seoul and an alleged mobilization of U.S. nuclear-capable B-52 bombers during training near the Korean Peninsula. North Korea calls the planned drills a rehearsal for invasion, a claim the allies deny. The State Department also said in a statement that civil rights leader Rev. Jesse Jackson had offered to travel to Pyongyang at the request of Bae's family. The State Department did not elaborate and referred questions to Jackson, whose spokesman didn't immediately respond to a request for comment. Bae has been held in North Korea for 15 months. Pyongyang accused him of smuggling in inflammatory literature and trying to establish a base for anti-Pyongyang activities at a border city hotel.