Swaziland's Senate voted its overwhelming support on Friday for a palace-authored constitution that permanently ensures monarchial power over the legislature, other arms of government and the security forces.
King Mswati III decreed the constitutional process in 1996, in a response to international pressure to bring democratic reform to the country.
The document, compiled by Mswati's brothers, Prince David Dlamini and Prince Mangaliso Dlamini, safeguards sub-Saharan Africa's last absolute monarchy from political opposition and retains a 31 year-old royal decree that bars Swazis from joining political parties.
Although the king's power remains inviolate, the constitution allowed for the popular recall of MPs who fall into disfavour with their constituencies. MPs voted to delete this section, but the move was overturned by the Senate. The higher legislative body is dominated by palace appointees and traditionalists.
Mswati is expected to sign the constitution into law this month.
The National Constitutional Assembly, an umbrella group of legal, human rights and labour organisations, is challenging the document in the High Court.
The group argues that the constitutional process was undemocratic and manipulated by royalists, and objects to the fact that human rights outlined in the constitution may be suspended at the King's discretion.