RIO DE JANEIRO -Leaders of the growing BRICS group of developing nations were set to gather in Rio de Janeiro on Sunday, calling for reform of traditional Western institutions while presenting the bloc as a defender of multilateralism in an increasingly fractured world.

Diplomats from the BRICS group of developing nations have agreed on a joint declaration of their leaders at a summit in Rio de Janeiro this week, three people familiar with the talks said on Saturday.

BRICS leaders set to discuss key global political issues in Rio de Janeiro, but questions over the bloc’s cohesion arise as Chinese President Xi Jinping and Russian President Vladimir Putin opt to skip the summit.