Cambodia is a step closer to choosing a new king, after approving legislation on the terms of succession.
King Sihanouk's successor will be chosen by a nine-member council
King Sihanouk announced his abdication last week, even though the law as it stood had no provision for such a move.
The new law calls for a new king to be approved within seven days of the incumbent's death, retirement or abdication, in this case by 14 October.
Prince Norodom Sihamoni, one of Sihanouk's sons, appears the most likely candidate to succeed his father.
The draft law on the succession was passed unanimously on Friday by the National Assembly, and was passed by the Senate on Monday.
It was then approved by the Constitutional Council and signed off by the acting head of state, Chea Sim.
Officials say the nine-member Throne Council will meet on Thursday to select the new monarch.
In a letter released over the weekend, King Sihanouk rejected pleas for him to stay on and said Prince Sihamoni was ready to accept the kingship.
Writing from Beijing, King Sihanouk said the 51-year-old Sihamoni - a former dancer - would make a suitable king because he was "a neutral person, not engaged in politics, and non-partisan".
Another of Sihanouk's sons, Prince Ranariddh, is head of the National Assembly and leader of the royalist Funcinpec party.
Laws for deciding succession still not agreed
Nine-member throne council decides between candidates
King thought to want Prince Sihamoni to succeed
Eldest son Ranariddh says he does not want the post
Prime Minister Hun Sen has also backed Prince Sihamoni, who recently gave up his post as Cambodia's ambassador to Unesco in Paris to join his father in Beijing, fuelling speculation that he was the favourite to accede to the throne.
The king's decision to abdicate shocked Cambodia, not least because the constitution, rewritten in 1993, does not cover the issue of abdication.
Since his announcement last Wednesday, leading figures in Cambodian life have signed petitions asking the king to stay on.
But in a letter read on radio and TV and posted on his website over the weekend, the king said he was too ill to continue.
In his first public comments on the abdication, Prime Minister Hun Sen had said that lawmakers must work "day and night to prevent the country becoming a republic".