JOHANNESBURG -- Russian President Vladimir Putin and Chinese President Xi Jinping were both absent as leaders from the BRICS group of emerging economies started a three-day summit in South Africa on Tuesday.

Putin's travel to Johannesburg was complicated by an outstanding International Criminal Court warrant for his arrest over the abduction of children from Ukraine. His participation as the bloc named for member nations Brazil, Russia, India, China and South Africa opened its first in-person meeting since before the COVID-19 pandemic came in the form of a 17-minute pre-recorded speech.

Xi, who was in South Africa and held a bilateral morning meeting with President Cyril Ramaphosa, did not join his host and the leaders of Brazil and India for a business forum at the primary summit venue. No reason was given for his absence, and Chinese Commerce Minister Wang Wentao read Xi's speech.

The summit's main session in Johannesburg's financial district of Sandton is scheduled for Wednesday, when Xi, Brazilian President Luiz Inacio Lula da Silva, Indian Prime Minister Narendra Modi and Ramaphosa were expected to meet as BRICS mulls a possible expansion.

The bloc already is home to 40% of the world's population and responsible for more than 30% of global economic output, and more than 20 nations have applied to join, according to South African officials, including Saudi Arabia, Iran and the United Arab Emirates.

Saudi Arabia's foreign minister, Prince Faisal bin Farhan, and Iranian President Ebrahim Raisi planned to attend the summit.

The five current member countries will have to agree on the criteria for new members before any countries are admitted, but a bigger BRICS is seen as a policy favoured by China and Russia amid their deteriorating relations with the West.

Brazil, Russia, India and China formed the bloc in 2009. South Africa was added in 2010.

While Foreign Minister Sergey Lavrov was representing Russia in Johannesburg, Kremlin spokesman Dmitry Peskov stressed that Putin would fully engage in the summit while participating remotely.

Local officials said Putin would "virtually" attend a Tuesday welcome dinner hosted by South Africa. The agenda also lists him as giving a speech via video link on Wednesday.

Overall, around 1,200 delegates from the five BRICS nations and dozens of other developing countries are are in South Africa's biggest city, and more than 40 heads of state were expected to take part in some of the summit meetings, according to Ramaphosa.

United Nations Secretary-General Antonio Guterres also was expected to attend.

On Tuesday's opening day, there were calls for more economic co-operation and collaboration in areas such as health, education and climate change while reflecting a growing sentiment in some parts of the world that institutions seen as western-led, including the the UN, the World Bank and the International Monetary Fund, do not serve developing nations.

While in South Africa's capital, Pretoria, earlier Tuesday for his meeting with Xi, Ramaphosa said he was seeking "Chinese support for South Africa and Africa's call for the reform of global governance institutions, notably the United Nations Security Council."

Africa and South America have no permanent representatives on the Security Council despite being home to nearly 2 billion people.

Xi, who has gradually resumed foreign travel after the lifting of his country's strict COVID-19 restrictions, joined Ramaphosa to watch a ceremonial parade by soldiers at the Union Buildings, the official seat of the South African government.

Xi made brief comments at the event, saying China was ready for more co-operation with Africa's most advanced economy "to take our comprehensive strategic partnerships to new heights."

BRICS officials have pushed back at suggestions the the bloc is taking an anti-West turn under the influence of China and Russia, saying it is rather looking out for the interests of the Global South.

But the BRICS stance is at odds with the United States and its western allies on a number of issues, not least over Russia's invasion of Ukraine. The European Union called on Xi, Lula, Modi and Ramaphosa to use this week's gathering to condemn Russia and Putin for the war in Ukraine, but that's unlikely to happen.

If anything, BRICS has been a forum for Russia to express its anti-western rhetoric, with Lavrov using a BRICS foreign ministers meeting in June to lambast the West for its "hegemony" and using "financial blackmail" to serve its "selfish interests."

A small protest against Russia's invasion of Ukraine was held Tuesday at a public park more than 3 kilometres (1.8 miles) from the summit venue.

The U.S. and EU will be closely monitoring events in Johannesburg, with the long list of countries lining up to join BRICS suggesting that the bloc's calls for a reorganization of the global governance structure might be hitting home with many.