Pledge of security is terminology to describe the international relations nowadays.  Rulings identified before by Muslim scholars needs to be revised according to the current international agreements.

Pledge of security

This refers to giving an unbeliever a pledge of safety, ensuring that his life and property are safe for a specified period.[1] Such a pledge may be common or private. The common is given to an unspecified number of people, such as the population of a certain area or a certain town or city. Like a truce agreement and the dhimmah pledge, none other than the Muslim ruler or his deputy can give such a pledge because it is a matter of public interest which only the ruler can decide. A private pledge of security is given to an individual or to a small number of people, normally less then ten.

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[1] Al-Nadawi, Al-Fiqh al-Muyassar, p. 209.