A friend of mine tells me that sustainable development should not be our priority, since it would impede economic growth, therefore perpetuating extreme poverty.
On the contrary, Jeffrey Sachs argues that both fights should be taken together and will benefit from being solved together:
"While targeted investments in health, education, and infrastructure can unlock the trap of extreme poverty, the continuing environmental degradation at local, regional, and planetary scales threatens the long-term sustainability of all our social gains. Ending extreme poverty can relieve many of the pressures on the environment. When impoverished households are more productive on their farms, they face less pressure to cut down neighboring forests in search of new farmland. When their children survive with high probability, they have less incentive to maintain very high fertility rates with the attendant downside of rapid population growth. Still, even as extreme poverty ends, the environmental degradation related to industrial pollution and the long-term climate change associated with massive use of fossil fuels will have to be addressed. There are ways to confront these environmental challenges without destroying prosperity (for example, by building smarter power plants that capture and dispose of their carbon emissions and by increasing use of renewable energy sources). As we invest in ending extreme poverty, we must face the ongoing challenge of investing in the global sustainability of the world's ecosystems."
(Jeffrey Sachs, "The end of poverty, economic possibilities for our time", chapter "Our generation's challenge").