Former Goldman Sachs economist Lord Jim O'Neill, who gave the BRICS bloc its name, has slammed the idea of the countries ever creating a common currency.
Luiz Inácio Lula da Silva, the Brazilian president, has called for a common trading note between Brazil, Russia, India, China, and South Africa to end the dollar's dominance as the world's premier reserve currency.
O'Neill, who coined the bloc's name in a 2001 paper, is not convinced.
In an interview with the Financial Times on Monday, he said, "It's just ridiculous. They're going to create a Brics central bank? How do you do that?"
In his speech, the economist spoke ahead of the BRICS 15th summit next week, in which the nations will decide whether to expand membership, as well as whether to propose a common currency - though South Africa denies this is on the agenda.
The term de-dollarization refers to efforts to promote the use of other currencies to undermine the greenback's dominance of global trade.
According to the International Monetary Fund, the dollar still accounts for nearly 60% of the world's foreign-exchange holdings, but its share has declined over the past two decades.
O'Neill criticized the dollar's influence on currency movements around the world in the interview. And speaking as a US citizen, I am hoping my country has learned a valuable lesson about throwing its weight around!
It's not ideal for the dollar's role at this point in time, he said. "You have all these economies depending on what the [US Federal Reserve] decides in its interests."
He does not see a future in which the renminbi, yen, or euro will surpass the US dollar.
"None of these things will ever happen until those countries want to have their currencies used by people in other parts of the world," he said.