A decision by Mali, Burkina Faso and Niger to quit West Africa's economic and political bloc reverses decades of regional integration, leaving millions of people in limbo, and is likely to deepen the three junta-led countries' ties with Russia.

The move to withdraw from the 15-member Economic Community of West African States (ECOWAS) could yet take time to implement, opening a door for negotiations.

But, if carried through, it is set to disrupt the region's trade and services flows, worth nearly $150 billion a year.