With French President Emmanuel Macron on Thursday announcing a revamp of France's military deployment in the Sahel, we take a look at this deeply troubled region and its role in world politics.
- What is it? -
The Sahel, meaning coast or shore in Arabic, is a vast region that stretches along the southern rim of the Sahara from the Atlantic to the Red Sea.
Wedged between the desert to the north and tropical forests and savannah to the south, the belt has a semi-arid climate.
- Where is it? -
There is debate over which countries actually belong to the Sahel.
But a core group -- Burkina Faso, Chad, Mali, Mauritania and Niger -- are gathered in an anti-jihadist alliance called the G5 Sahel.
Other definitions of the region take in parts of Senegal, Nigeria, Sudan, South Sudan and Eritrea.
- Jihadist hunting ground -
With vast stretches of inhospitable desert and porous borders, the central Sahel is a hunting ground for armed groups, rebels, jihadists and criminal gangs.
Jihadist violence erupted after a rebellion in northern Mali in 2012, with the conflict spreading to the centre of the country and then to neighbouring Burkina Faso and Niger, claiming thousands of lives and displacing hundreds of thousands of people.
One of the bloodiest flashpoints is the so-called "tri-border area" where the frontiers of Niger, Mali and Burkina converge.
Several anti-jihadist military operations have been launched in the region, including the French operation Barkhane and the G5 Sahel force, which includes units from the five countries' armies.
Macron said Thursday that "our commitment in the Sahel will not continue in the same way" as in recent years with the 5,100-strong Barkhane deployment.
- Climate change -
As the world battles climate change, the effect of global warming is around 50 percent greater in the Sahel. In the last quarter of the 20th century, the region suffered the worst droughts anywhere on the planet.
This has contributed to a staggering 90 percent decline of the surface of Lake Chad over the past six decades, and a race is on to stop the main source of fresh water to 40 million people across four countries drying up.
In February 2019, countries set down a plan to invest $400 billion in fighting climate change in the Sahel by 2030.
- Population pressure -
The region, which is wracked by poverty, has one of the highest demographic growth rates in the world.
The population of the G5 Sahel region is expected to more than double to around 170 million by 2050, according to the United Nations.
Amid the unrest, poverty and climate change, the UN said internal displacement had increased 20-fold in less than two years and the number of families facing hunger has tripled.
The United Nations has warned of a heightened risk of famine in Burkina Faso, along with northeastern Nigeria and South Sudan and also a high hunger risk in both Mali and Niger.
Problems have been exacerbated by the Covid-19 pandemic, and vaccination campaigns are essentially at a standstill.