A no-deal Brexit, which has no democratic mandate, could be imposed upon the people of this country without approval by UK or Scottish Parliament.

https://www.heraldscotland.com/news/17774570.boris-johnson-considering-option-suspending-uk-parliament-mid-october-stop-mps-blocking-no-deal-brexit/

UN Declaration on the Granting of Independence to Colonial Countries and Peoples

1. The subjection of peoples to alien subjugation, domination and exploitation constitutes a denial of fundamental human rights, is contrary to the Charter of the United Nations and is an impediment to the promotion of world peace and co-operation.
2. All peoples have the right to self-determination; by virtue of that right they freely determine their political status and freely pursue their economic, social and cultural development.
3. Inadequacy of political, economic, social or educational preparedness should never serve as a pretext for delaying independence.
4. All armed action or repressive measures of all kinds directed against dependent peoples shall cease in order to enable them to exercise peacefully and freely their right to complete independence, and the integrity of their national territory shall be respected.
5. Immediate steps shall be taken, in Trust and Non-Self-Governing Territories or all other territories which have not yet attained independence, to transfer all powers to the peoples of those territories, without any conditions or reservations, in accordance with their freely expressed will and desire, without any distinction as to race, creed or colour, in order to enable them to enjoy complete independence and freedom.
https://www.un.org/en/decolonization/declaration.shtml