In a broad sense, sanctions include ‘unfriendly acts’ of calling back diplomats or closing diplomatic missions. Such measures are often mirrored by equivalent measures from the sanctioned state.
Financial sanctions may include freezing assets of individuals, terminating financial support to the sanctioned state, closing or pausing joint projects.
Economic sanctions may range from prohibitions on importing certain goods from the sanctioned state to complete trade embargoes and termination of economic cooperation.
Travel-related sanctions include travel bans and visa restrictions, effectively preventing sanctioned individuals from entering certain territories.
Sanctions involving the use of force (e.g., placement of armed forces) can only be adopted by a United Nations Security Council Resolution. The only other permitted case of using force in international law is self-defense.