The Brics bloc of developing nations likes to boast that it represents nearly half the world’s population, but its annual summit this weekend in Brazil highlighted a drawback of its fast expansion: the complexity of reaching agreement.

The bloc — comprising Brazil, Russia, India, China and South Africa until 2023 — has more than doubled in size, as Saudi Arabia, Egypt, Iran and others swelled its ranks. Some new members have injected fresh divisions into the Brics, which was already struggling for coherence and split between democracies and autocracies.

Brics leaders focused their declaration on Sunday on long-standing demands for reforms of global governance, including fairer geographical representation on the UN security council, the IMF and the World Bank to reflect the increased weight of emerging markets in the global economy.