Myanmar's ruling junta has used new election laws to officially annul the result of polls in 1990 that were won by Aung San Suu Kyi's opposition party, state media said on Thursday.
The regime is planning to hold elections later this year, the first in the country since Suu Kyi's National League for Democracy swept to victory two decades ago.
The NLD was prevented from taking power by the military at the time but the result has not been formally cancelled until now. Suu Kyi has spent 14 of the subsequent 20 years in detention.
"The result of the multi-party democracy elections, held under a deleted law, is automatically abolished as it is not in accordance with the constitution," said a clause in one of the laws printed in state newspapers.
The junta enacted the long-awaited new electoral laws on Monday and details have emerged during the week.
The most controversial of them says that the NLD must expel Suu Kyi from its ranks or be dissolved on the grounds that a person serving a prison term cannot be a party member.
Suu Kyi was sentenced to three years' jail in August over an incident in which a US man swam to her lakeside home, but her sentence was commuted by junta supremo Than Shwe to 18 months under house arrest.
Another law says that the junta itself will hand-pick members of the country's new electoral commission.
No date for this year's elections has been set but they are expected to be in October or November.