The United Nations Secretary-General has warned the enduring legacy of colonialism — marked by entrenched economic exploitation, racism, inequality and exclusion from decision-making — continues to shape the world's remaining 17 non-self-governing Territories.

More than six decades after the UN launched its formal decolonisation drive, Secretary-General Antonio Guterres has urged a renewed commitment to complete unfinished business in ending all colonial rule "since its earliest days" as a core objective of the global organisation.

"This organisation was created as a place where nations could meet as equals and not as rulers and ruled," Mr Guterres said in a statement.

A territory is considered non-self-governing when it has yet to achieve either independence, free association or full integration with another state when its people have not fully exercised their right to self-determination; and also when governance responsibility rests with an external authority.

Marking the UN's opening session of 2026, Mr Guterres has called for inclusive dialogue, youth leadership and urgent climate action to guide the future of territories.

"Our world has come a long way, with well over 100 nations gaining independence since 1945," the UN's Chef de Cabinet, Courtney Rattray, said on behalf of the Secretary-General for the Special Committee on Decolonisation on Tuesday.

"Yet the legacy of colonialism has left profound scars through the deeply-rooted mechanisms of economic exploitation, as well as in the form of racism, inequality and persistent exclusion from decision-making bodies."

When the UN was first established in 1945, some 750 million people — nearly one-third of the world's population at the time — lived in non-self-governing Territories, dependent on colonial powers which were ruled predominantly from Europe.

Almost two million people, more than 450,000 of them Indigenous, remain, including from American Samoa, French Polynesia, Guam, New Caledonia and Tokelau, which are ruled by either France, New Zealand or the US.

Other non-Indigenous territories also fall under the reign of the United Kingdom.

Some of the Indigenous territories have a long and complicated history.

French Polynesia was relisted a non-self-governing Territory in 2013, making the group of 121 Pacific islands eligible for a UN-backed independence referendum.

The relisting was made after the Indigenous opposition of colonialism was voiced and supported by the Polynesian Leaders Group, Pacific Conference of Churches, the Women's International League for Peace and Freedom, the Non-Aligned Movement, the Melanesian Spearhead Group and the World Council of Churches.

Indigenous Kanaks are also pressing France for New Caledonia's independence.

The French government have been negotiating the terms of reference and rule of law towards sovereignty with the Kanak and Socialist National Liberation Front.

In 1960 the UN's General Assembly first adopted the Declaration on the Granting of Independence to Colonial Countries and Peoples (the Declaration) resolution, which was a landmark text at the time.

The following year the Special Committee on Decolonisation was established, as a subsidiary organ of the Assembly devoted to the issue.

Mr Guterres laid out three priorities for the Special Committee regarding the implementation of the Declaration to guide the remaining non-self-governing Territories.

He called for inclusive dialogue among non-self-governing Territories, administering powers, member states and all stakeholders.

"This process must be steered by the unique aspirations and needs of each Territory and take place on a case-by-case basis," Mr Guterres said.

He also urged young people to play a significantly central role as "the vision and leadership of the next generation is vital to building a productive and inclusive future" in addition to an urgent need for climate action.

Most territories are small islands where rising sea levels, coastal erosion and frequent extreme weather are exacting a heavy toll, Mr Guterres noted.

Upon re-election for this year's session, UN Special Committee on Decolonisation chair, Mennisa Rambally, said the UN's "decolonisation agenda remains unfinished".

"The cause of decolonisation is not merely an institutional obligation, but it is a fundamental right and expression of the United Nations' founding purpose," she said.

"It embodies our shared belief in dignity and equality."

Indonesia also joined other speakers at Tuesday's session in voicing its commitment to decolonise territories as a "legal, political and moral" imperative.

Its delegation called for "frank and constructive" dialogues which should be underpinned by a "spirit of mutual respect".

The UN once endorsed Indonesia annexing the former Dutch New Guinea — commonly referred today as West Papua — in 1963 at the conclusion of its colonisation.

Indonesia's ruling of the territory has remained highly contested by Indigenous Papuans across Western New Guinea amid their ongoing fight for independence.