(AFP) - South Africa's president on Wednesday sought to ease "tensions" between rival members of the Zulu royal family after a court ruled that the state's recognition of King Misuzulu Zulu was "unlawful".

President Cyril Ramaphosa will appeal Monday's Pretoria high court ruling that his move to recognise Misuzulu Zulu at an elaborate ceremony in October 2022 was "unlawful," the presidency said.

The king's older brother, Prince Simakade, sought the ruling. The 49-year-old king had faced other challenges after being nominated to take over from his father, King Goodwill Zwelithini, who died in 2021 after ruling for 52 years.

Ramaphosa's office said Misuzulu Zulu would remain monarch for the more than 10 million Zulu people while the appeal is launched.

"President Ramaphosa calls on all members of the Royal family to continue working for the unity" of the Zulu people "and to prioritise the interest of his majesty's subjects," said a statement released by presidential spokesman Vincent Magwenya.

"It is vital that all due processes are allowed to reach their natural conclusion without inflaming tensions."

- Royal investigation -

The court ordered Ramaphosa to set up an investigation into whether Misuzulu Zulu's tumultuous accession was in line with customary laws.

Experts are divided over what impact it will have on the king's standing but they said a decision would take time.

Zulu accessions rarely pass smoothly.

After Misuzulu's nomination in March 2021, a bitter feud, including court challenges, between rival claimants delayed the traditional coronation until August 2022.

Two months later, Ramaphosa held his grand ceremony to recognise the king.

Prince Simakade, born out of wedlock but the late king's eldest son, has been publicly championed by some dissenting relatives.

Misuzulu's mother, the favourite third wife of the late king, was from the Swati royal family. Some experts say her children had priority under Zulu custom.

Last year Misuzulu Zulu called for "peace and unity" after a series of unexplained deaths just before his coronation.

In July, he denied being poisoned, after the sudden death of a close adviser who ingested a toxic substance.

"This situation is going to escalate because there is a lot at stake" historian and cultural analyst Pitika Ntuli told AFP. "There are resources involved... and land."

Misuzulu Zulu inherited nearly 30,000 square kilometres of land -- almost the area of Belgium -- which is managed by a trust from which he can receive revenues.

Known for his lavish lifestyle, King Goodwill Zwelithini received about $82,000 a year for himself along with a budget of $4.2 million to run his kingdom.

"Zulu succession nowadays is viewed in a very western way," University of KwaZulu-Natal African languages professor and cultural expert Gugu Mazibuko told AFP.

"We can't be compared to England where there is a clear line of succession, our culture is vastly different," she said.

The Zulu nation is South Africa's biggest ethnic group. The monarch is recognised by South Africa's constitution. While the king has no executive powers, he exercises widespread moral authority.

According to Ntuli, South Africa failed to properly process customary laws at the advent of democracy in 1994, leaving many "loopholes".

While it is not the first time the Zulu throne is contested, "the difference is modern courts were not involved," Mazibuko said.

© Agence France-Presse