Whilst many definitions fall under the term ‘conflict of interest’ in addressing employees or representatives of public, private, governmental and non-governmental organizations (assorted documents may be consulted here), a common core is presented in the Review of Mechanisms and Policies Addressing Conflict of Interest in the United Nations System, which defines it as:
"circumstances in which international civil servants, directly or indirectly, may benefit improperly, or allow a third party to benefit improperly, from their association with their organization."
It is important to note in regard to the NGO Forum Steering Committee, that its members are not international civil servants, and their work is of voluntary character. Nevertheless, as they are chosen to represent their geographic regions, and the ICH NGO Forum functions within the UNESCO-ICH system, their responsibility to comply with UN standards is higher than those of regular members of NGO Forum that solely represent their organizations.
Further important information related to the UN definition of conflict of interest may be found in the above-mentioned document under chapter I.B (paragraphs 12-18).*
*
https://www.unjiu.org/sites/www.unjiu.org/files/jiu_rep_2017_9_english.pdf