BRICS leaders will meet in Rio de Janeiro from Sunday, with the bloc depleted by the absence of China's Xi Jinping, who is skipping the annual summit of emerging economies for the first time in 12 years.

The grouping -- often seen as a Chinese-driven counterbalance to Western power -- meets as members face imminent and costly tariff wars with the United States.

Conceived two decades ago as a forum for fast-growing economies, the BRICS have come to be dominated by Beijing, which grew much faster and larger than the rest.

China has not said why Xi will miss the summit, a first since he became president in 2012.

"I expect there will be speculation about the reasons for Xi's absence," said Ryan Hass, a former China director at the US National Security Council who is now with the Brookings Institution think tank.

"The simplest explanation may hold the most explanatory power. Xi recently hosted Lula in Beijing," said Hass.

The Chinese leader will not be the only notable absentee. War crime-indicted Russian President Vladimir Putin is also opting to stay away, but will participate via video link, according to the Kremlin.

So too will Iran's President........

© International Business Times