Kautilya's Arthashastra 9.6.45

9.6.45

itareṣu maitrīṃ bruvāṇāḥ "tvam eteṣāṃ ghātayitavyaḥ" ity upajapeyuḥ //

Or such kings as are possessed of enthusiasm and power may be told: "Seize the country of this king, our treaty of peace standing as before." Then spies should inform the particular king of the attempt of these kings and cause the destruction of the commissariat and of the followers of one of these kings. Other spies, pretending to be friends, should inform these kings of the necessity of destroying the particular king.