Arthashastra
दुर्गाच् च अनवरोध क्षमम् अपनयेत्, प्रत्यादेयम् अरि विषयं वा प्रेषयेत् ॥
One should remove from a fortress whatever is incapable of withstanding a siege, or send it away to enemy territory where it may later be recovered.
english translation
durgAc ca anavarodha kSamam apanayet, pratyAdeyam ari viSayaM vA preSayet ॥
hk transliteration by Sanscript