Russian President Vladimir Putin with International Monetary Fund managing director Christine Lagarde at the G20 summit in 2013 in St. Petersburg, Russia. Ramil Sitdikov/Host Photo Agency via Getty Images Russian President Vladimir Putin ratified an accord Saturday to set up a $100 billion reserve fund for the so-called BRICS — the leading emerging economies Russia, China, Brazil, India, and South Africa.

Moscow is expected to contribute $18 billion to the reserve, well behind the $41 billion China has promised to pour into the fund, which was set up after an agreement signed in July in Brazil.

The emerging economies also plan to form their own international bank based in Shanghai to challenge western dominance over international money markets.

"The accord on the creation of a common reserve fund for BRICS countries has been ratified," a document from the Kremlin quoted by RIA Novosti news agency said.

The fund is meant to shield the BRICS against "short-term liquidity pressures" and promote greater cooperation between the five member countries.

Russia — which has suffered huge currency fluctuations since the outbreak of the crisis in Ukraine — sees the fund as an alternative to international financial institutions like the International Monetary Fund and World Bank that are dominated by the US.

The BRICS countries between them account for 40% of the world's population and a fifth of the planet's gross domestic product.