The outgoing prime minister of Samoa Tuilaepa Sailele Malielegaoi is refusing to concede that he lost the election.
On Friday the Court of Appeal ruled that the FAST Party, which won 26 seats in the 9 April election, was the country's legitimate government.
The Court was ruling on whether an impromptu swearing in in a marquee on the grounds of parliament was legal.
It said it was and that from that date the FAST party had been the legitimate government of Samoa.
FAST had been forced into the unorthodox swearing in after being barred from entering parliament.
The Head of State had countermanded his own order to convene parliament but the Court of Appeal said he acted unconstitutionally.
Tuilaepa has told local media that the Court of Appeal decision yesterday is unconstitutional.
Meanwhile, the FAST cabinet is meeting this morning and it is planning its first actions once it formally assumes power.
Congratulations from Ardern
New Zealand's Prime Minister Jacinda Ardern has congratulated Samoa's Prime Minister-elect, Fiame Naomi Mata'afa, on her victory.
Ardern said New Zealand has a special relationship with Samoa, anchored in the Treaty of Friendship.
She said she looks forward to working with Samoa's new government.
Ms Ardern also acknowledged the outgoing prime minister saying he delivered so much to Samoa and the region.