(AFP) - Namibia's President Hage Geingob, a veteran of the country's liberation struggle and its first post-independence prime minister, died on Sunday, his office announced.

Tributes to the 82-year-old statesman poured in from African leaders who saw him as a hero of the anti-apartheid struggle.

Recently, he supported South Africa's complaint against Israel under the Genocide Convention and condemned Namibia's former colonial ruler Germany for opposing the case.

Geingob, who was serving his second term as president, revealed last month that he was being treated for cancer.

Namibia's acting president Nangolo Mbumba announced the death, saying "our beloved Dr. Hage G. Geingob, the President of the Republic of Namibia, has passed on today."

"At his side, was his dear wife Madame Monica Geingos and his children."

This triggered an outpouring of tributes from around the continent, including from leaders who worked alongside him in the struggle to free southern Africa from apartheid rule.

President Cyril Ramaphosa of South Africa said: "Today, South Africa joins the people of our sister state Namibia in mourning the passing of a leader, patriot and friend of South Africa.

"President Geingob was a towering veteran of Namibia's liberation from colonialism and apartheid.

African Union Commission chair Moussa Faki Mahamat sent his condolences over the loss of "an inspiring Pan-Africanist leader who led his country with humility, determination & courage".

- 'Visionary leader' -

President William Ruto of Kenya echoed this praise.

"He was a believer of a unified Africa and strongly promoted the continent's voice and visibility at the global arena," he said.

Kenya's former president Uhuru Kenyatta described Geingob as "a distinguished servant of the people, an outstanding statesman and a great leader full of wisdom".

And the director of the World Health Organization, Tedros Adhanom Ghebreyesus, hailed Geingob's work to improve healthcare for Namibians, dubbing him a "visionary leader".

Beyond Africa, Russian President Vladimir Putin said in a statement he would "forever fondly remember this wonderful man".

And writing on X, formerly Twitter, Belgium Prime Minister Alexander De Croo called Geingob "a liberator and a leader."

First elected president in 2014, Geingob was Namibia's longest-serving prime minister and third president.

In 2013, Geingob underwent brain surgery, and last year he had an aortic operation in neighbouring South Africa. He had been receiving treatment at Lady Pohamba Hospital in Windhoek.

"The Namibian nation has lost a distinguished servant of the people, a liberation struggle icon, the chief architect of our constitution and the pillar of the Namibian house," said Mbumba.

"At this moment of deepest sorrow, I appeal to the nation to remain calm and collected while the government attends to all necessary state arrangements, preparations and other protocols."

He said the cabinet would convene immediately to make the necessary state funeral arrangements.

Last month, Geingob threw his weight behind South Africa's challenge against Israel's military campaign in Gaza, under the Genocide Convention in the UN's top court.

In particular he singled out for criticism Germany, Namibia's former colonial ruler and an outspoken critic of South Africa's case alleging Israel has breached the convention.

Lamenting "Germany's inability to draw lessons from its horrific history", the Namibian leader accused Berlin of defending "genocidal and gruesome acts".

Germany massacred more than 70,000 Indigenous Herero and Nama people in Namibia between 1904 and 1908, in what many historians consider the first genocide of the 20th century.

In May 2021, after more than five years of negotiations, Germany said it recognised it committed a genocide in the territory it had colonised from 1884 to 1915.

- Independence struggle -

Born in a village in northern Namibia in 1941, Geingob was the southern African country's first president outside the Ovambo people, which makes up more than half the country's population.

In his early years he took up activism against South Africa's apartheid regime, which at the time ruled over Namibia.

In 1964 he was appointed representative for the SWAPO liberation movement at the United Nations.

He spent almost three decades in Botswana and the United States, returning to Namibia in 1989 to lead SWAPO's election campaign in his now independent homeland.

Namibia is to hold presidential and national assembly elections towards the end of the year.

© Agence France-Presse