US president-elect Donald Trump has threatened to impose "100 per cent tariffs" on a group of nine developing nations if they create a rival currency to the US dollar.
His threat on Saturday was directed at the so-called "BRICS" group, which is a coalition of non-Western countries that includes major world powers such Russia and China.
Writing on social media, Trump demanded a "commitment" from the group's members that they would not move away from US dollars.
"We require a commitment from these Countries that they will neither create a new BRICS Currency, nor back any other Currency to replace the mighty US Dollar," he said.
The statement came in the wake of a BRICS summit in Kazan, Russia, where developing countries discussed boosting non-dollar transactions and strengthening local currencies.
But whether the group could dethrone the US dollar, which has been the world's most used currency since the end of the World War II, is still up in the air.
Here's a look at what the BRICS group wants, and how it's challenging the world's reliance on US currency.
What is the BRICS group?
It's an informal group of nine countries that want emerging economies to have more influence on international politics.
The founding members, Brazil, Russia, India and China, held the first leaders summit in 2009 under the acronym "BRIC". South Africa joined in 2010, making it "BRICS".
Egypt, Ethiopia, Iran, and the United Arab Emirates have since also become members.
The heads of state and governments of these countries convene annually, with members taking it in turns to serve as chairman of the group each year.
Türkiye, Azerbaijan and Malaysia have applied to become members, while several other countries, including Saudi Arabia, have expressed interest in joining.
Why does BRICS matter?
Together, the group accounts for more than 37 per cent of the global economy and some 40 per cent of the world's population.
BRICS member nations include some of the largest importers of oil (China, India) and some of the largest exporters of it (Russia, UAE).
After their first summit in Russia 15 years ago, BRIC countries released a joint statement saying "emerging and developing economies must have a greater voice and representation in international financial institutions".
The group sees BRICS as an alternative to global bodies that it argues are dominated by Western powers, such as the World Bank and International Monetary Fund (IMF).
In 2014, BRICS members set up their own New Development Bank to lend money to developing countries to boost their infrastructure and sustainability.
They hope that alternative lending institutions can increase cooperation between emerging economies and reduce dependence on Western-led funding sources.
Over the years, members of the group have also pursued policies to reduce their reliance on US dollars, with Russia, for example, de-dollarising its reserves and trade after being heavily sanctioned in 2022 for invading Ukraine.
In 2023, Brazilian President Luiz Inacio Lula Da Silva questioned why all countries had to base their trade on US currency, while later this year, Russian President Vladimir Putin accused the US of "weaponising" its currency.
"It's not us who refuse to use the dollar," Mr Putin said in October. "But if they don't let us work, what can we do? We are forced to search for alternatives."
Can BRICS really drop the US dollar?
For now, BRICS countries have not been able to reduce global reliance on the US dollar, a study by the Atlantic Council's GeoEconomics Center shows.
The findings report of the Dollar Dominance Monitor project said the dollar's role as the primary global reserve currency was "secure in the near and medium term".
The US currency represents roughly 58 per cent of the world's foreign exchange reserves, according to the IMF, and major commodities such as oil are still primarily bought and sold using dollars.
The Atlantic Council report points out BRICS members have turned their attention away from a shared currency and toward new cross-border payment systems with the goal of creating a more diverse financial network.
"The dollar continues to dominate foreign reserve holdings, trade invoicing, and currency transactions globally," the report said.
"All potential rivals, including the euro, have a limited ability to challenge the dollar in the immediate future."
However, the study identified the BRICS group as "a potential challenge to the dollar's status" because of its members' intent to trade more in national currencies and because of their growing share of the global economy.
Among the BRICS currencies, China's renminbi has the greatest potential of competing with the dollar as a trade and reserve currency, the report said.
That's partly because China has been able to expand the use of its alternative cross-border payment system known as CIPS, which is a renminbi settlement mechanism that was built to rival the global bank messaging network SWIFT.
The SWIFT system, which mostly involves movements of the dollar, is still by far the dominant player, with more than 11,000 connected banks.
Meanwhile, negotiations around an intra-BRICS payment system are still in the early stages, though the report notes members have reached bilateral and plurilateral agreements with one another.
"These agreements are likely difficult to scale due to regulatory and liquidity issues but may form the basis for a currency exchange platform over time," it said.
