Conduct of a Neutral King, mentions in the chapter XVIII of Book VI in Arthashastra, that whenever the neutral king thinks of uniting with the Madhyama king, both can pose a danger to the conqueror should be alert enough and make all efforts to break the tie of confidence among both the kings. The conqueror can frustrate the desires of the neutral king to overreach an enemy or to help a friend or to secure the services of the army of another neutral king. As such those who are inimical to the conqueror are the kings of wicked character and who therefore always harmful, a rear enemy in combination with the frontal enemy, a reducible enemy under troubles and the one who is watching the troubles of the conqueror to invade him at the right hour.
Conduct of a Neutral King further marks that those who are friendly to the conqueror are the one who marches with him with the same end in view, one who marches with him with different ends in view, one who wants to combine with the conqueror to march against one common enemy, one who marches under an agreement of peace, one who marches with a set purpose of his own, one who rises with others, one who is ready to purchase or sell either the army or the treasury and who is capable of adopting a double policy. In case of the Neighbouring kings who can serve as servants to the conqueror king mainly include those who under the apprehension of attack from a powerful king, or the one who is situated in between the powerful conqueror and a strong enemy, the rear enemy of a powerful king or the one who has voluntarily surrendered one self to the powerful king for protection or under fear surrendered to the powerful enemy and has been subdued. The same is the case with the kings who are situated on the immediate neighbourhood of the enemy king.
Conduct of a Neutral King then entails that the conqueror should as far as possible help those who as a friend hold the same end in view as the conqueror has against the enemy and hold him at bay; whenever the friend of the conqueror, having put down his enemy turn out to be non submissive the conqueror should incur displeasure of the neighbour and the king next to the neighbour; the conqueror may continue to help those who are obedient to him even after winning the war; and at the same time should never help the friend who is deteriorating; whenever the conqueror finds his friend to be desirous of being wealthy after the war, should immediately remove the cause of his friend`s flight; the conqueror should further make all efforts to provide security to those who are depended on him. These are some of the conditions which the conqueror should follow in observing the conduct of the neutral king.
Thus, Conduct of a Neutral King, like the conduct of the Madhyam King, alerts the conqueror to be vigilant towards the intentions of the neutral king and his growing power which should not endanger the position of the conqueror in any way.