On the day of the general election, you reported on the referendum in Bougainville, a chain of Pacific islands that has voted for independence from Papua New Guinea (‘In the mood for celebration’: Bougainville islanders vote to be world’s newest nation, 12 December). Independence has to be agreed by the government of PNG, but if it refuses then the matter will go to the United Nations. The UN charter guarantees the “self-determination of peoples” and will apply sustained pressure on a nation that disregards a legitimate wish for self-determination by part of its territory.

This happened in Timor-Leste where the UN eventually sponsored a referendum in 1999 which secured the country’s independence from a highly reluctant Indonesia in 2002.

The SNP has always campaigned for independence from the UK. Winning 48 of the 59 Westminster seats is a clear expression of a wish for self-determination. If the UK government refuses to allow a referendum and the matter goes to the supreme court, it will have to take account of the UN charter.

If the court decided a referendum is a requirement of international law but a Johnson government still refused, Scotland could take the matter to the UN through other sympathetic countries. Not being a matter relating to “the maintenance of international peace and security” (article 24 of the UN charter), it wouldn’t go to the security council, where the UK has a veto. It would go to the general assembly, where a resolution requiring a referendum would be likely to pass by a large majority. If the resolution is expressed in binding terms, the UK would have to comply or suffer huge reputational damage.

I would expect to see a Scottish independence referendum within the life of the new government. If it goes the SNP’s way, Scotland would join the community of nations soon after Bougainville.

Laurie Smith

Carshalton, London