The effects of Covid-19 have worsened the plight of about 31.4 million people in the Sahel last year, with 14 million -- double a year earlier -- acutely food insecure, UN humanitarians said.

"This year, humanitarian needs will once again grow in the Sahel," the UN Office for the Coordination of Humanitarian Affairs (OCHA) said in a release.

"Humanitarian action -- food, shelter, education, protection and medical services -- matters, not just because it saves lives but also because it sends the message that people care about what is happening in the Sahel."

"Peace, good governance and development are needed to make a meaningful change in the lives of millions of people in the southern fringes of the Sahara, said OCHA.

Insecurity has increased in Burkina Faso, Mali, western Niger -- the Central Sahel -- where the number of internally displaced people has risen 20-fold since 2018, it said.

The humanitarian office said violent incursions in the Lake Chad Basin region continue to increase internal displacements and the need for humanitarian assistance.

Northeastern Nigeria and Burkina Faso are facing the risk of famine, according to early warning analysis by the Food and Agriculture Organization and the World Food Programme.

Of the 6.3-billion-U.S. dollar appeal by OCHA to respond to needs in the Sahel in 2020, only 46 percent was raised, said the agency.