The objective of this paper is to analyze the mechanics of object pulling by more than one robot using flexible tools such as rope. The concept of nonprehensile pulling where an object is not completely tied by a rope such that an object can roll or slide along the rope is the main focus of this study. The necessary condition for a stable nonprehensile pulling is defined. The mechanics of nonprehensile pulling is used to define the set of feasible motion directions of the object. This set of feasible motion directions of the object is then used for planning the coordination between two robots such that the task of object transportation can be achieved. The proposed analysis can also be extended for multiple objects transportation. This study provides a necessary basis required in developing an algorithm for a group of robots to autonomously cooperate such that the pulled object can be positioned and oriented in the 2D space.