In: Economics
Intergovernmentalism
It refers to any form of interaction between states that takes place on the basis of sovereign independence. These include treaties and alliances as well as leagues and confederations.
Supranationalism
It refers to the existence of one authority that is higher than that of the nation state and capable of imposing its will on.
Differences
In case of Intergovernmentalism all states are recognised as equal and there is no legal framework. There are non-state actors such as NAFTA, ASEAN and NATO. But in case of Supranationalism there's a higher authority than the nation-state members and thus has legal enforceability such as the European Court of Justice in the EU.
In case of Intergovernmentalism there's a means of maintenance of state sovereignty such as the UN general assembly. There's a national identity and clear democratic accountability but in case of Supranationalism, this means sovereignty will be pooled such as the EU commission. There will be overlapping identities and the so called 'democratic defecit' - slippery slope to world government.
There is difference in Voting systems of Intergovernmentalism and Supranationalism. In casr of Intergovernmentalism the decision making is done unanimously. Each country has a veto power. Example Worl Trade Organization. But in case of Supranationalism there is qualified majority voting. Example Like in European Union Council of members.
UN as Intergovernmentalism
Activities in the United Nations does not reflect Supranationalism. United Nations is just an ordinary intergovernmental organization which has states as its members. United Nations had the power to issue resutions but these resolutions are non binding. These resolutions are recommendations which signifies the role of member states. The United Nations does not function like a full fledged country. It can be called as an accomodation for its member countries to co-operate. Also, The UN charter's recognition of state sovereignty limits the UN character of Supranationalism.