CLICK BEETLE Phase II was initiated by Commander Task Force 96 (COMNAVFORJAP) Operation Order (OPORDER) 301-68 of January 3, 1968.
Phase I had successfully tested the operational feasibility and political implications of using one small trawler-type ship as a naval surveillance and intelligence collection unit.  Phase II expanded the program to use two ships (USS Banner and USS Pueblo) to provide continuous coverage of a selected area of operations.  The program’s objectives also included testing Soviet reaction to the continuous presence of a U.S. intelligence collection ship in Soviet naval operating areas. It was expected that the experience gained from Phase II, and the procedures and equipment developed therefrom, would lead to the implementation of Phase III – the employment of more AGERs.

During the CLICK BETTLE Phase II operations, the SIGINT collection ship were specifically required to:

(1) Remain a minimum of one mile outside the Communist-claimed  territorial waters – closer than 13 nautical miles from Communist-claimed land;
(2) Avoid any action that would be considered harassment and not close communist ships to within 500 yards except for briefly closing to 200 yards as necessary for visual or photographic coverage of items of unusual interest;
(3) Avoid collisions with Communist ships; and
(4) Avoid actions that could be construed  as provocative, including the display of weapons in a manner that could be misinterpreted as an intention to use them.

Code words pertinent to the CLICK BEETLE Phase II operations included BREEDER, assigned by the Chief of Naval Operations for AGER SIGINT collection operations in Atlantic and Pacific Fleets; ICHTHYIC, assigned by the Commander in Chief Pacific; and GRAVY BOAT, assigned to unclassified research operations in an ocean environment in support of research programs.  PINKEROOT ONE was the code ward specifically assigned to Pueblo’s first mission.

The mission of the Naval Security Group Detachment (NAVSECGRUDET) on board AGER during deployment was to intercept, exploit, and report on foreign electromagnetic emissions for SIGINT purposes.  The detachment’s paramount function was to provide direct support to the AGER commanding officer, and its secondary function was to satisfy specific fleet and national collection requirements. Routine operational control for SIGINT functions was exercise by Director Naval Security Group, Pacific.  Technical control of SIGINT operations was exercise by the National Security Agency.  Intelligence coordination with COMAVJORJAP and Commander Naval Forces, Philippines was effected by CINCPATFLT and COM7THFLET, as required.  Command of Naval Security Group Detachment was exercised by the AGER commanding officer through the officer in charge of the detachment.

The decision to assign Pueblo to an area off North Korea was based on several considerations:

(1) Weather conditions in January are marginal off Petropavlovsk and Vladivostok, so those areas were rejected;
(2) Operations off the Chinese coast were eliminated because planners were uncertain as to how Pueblo, on her first mission, would react to the harassment and intimidation to be expected from the Chinese;
(3) The Tsushima Strait was rejected because previous missions had obtained only marginal results; and
(4) There were priority intelligence collection requirements on North Korea against which it was thought Pueblo could collect.

Source: A Century of U.S. Naval Intelligence
Edited by Mario Vulcano