It is extremely rare for Westminster to impose such measures, but not without precedent. The UK forced its Caribbean territories to abolish the death penalty in 1991 and to decriminalise homosexuality in 2000.
Before a major UK summit to be attended by 50 countries and international institutions, a powerful coalition of anti-corruption organisations is urging Cameron to take action that would, if they failed to do so voluntarily, force the overseas territories and crown dependencies to introduce central public registers of company ownership, allowing law-enforcement agencies to identify their true beneficiaries.
Downing Street disclosed on Saturday that the presidents of Afghanistan, Colombia and Nigeria would attend the summit, along with the Norwegian prime minister, on Thursday.
A spokesman said Cameron wanted all those present to sign the first global declaration against corruption, which would commit them to working together to tackle it, acknowledging that corruption undermines efforts to end poverty, promote prosperity and defeat terrorism and extremism.
In the wake of the Panama Papers scandal, which revealed the extent to which the likes of the British Virgin Islands (BVI) were being used to hide money offshore, the prime minister is being urged to set a timetable for imposing stringent anti-corruption laws on Britain’s tax havens.