Khartoum - About 224 million people are suffering from malnutrition across Africa as climate change and conflicts heighten food insecurity across the continent, a top UN food agency official said Monday.The official, speaking at a conference on Africa organised by the UN's Food and Agriculture Organisation (FAO), said the situation was a "cause of concern" as the continent's population was expected to reach 1.7 billion by 2030."Under-nourishment appears to have increased from about 21% to nearly 23% between 2015 and 2016," Bukar Tijani, FAO's assistant director general for Africa, said at the regional conference that opened on Monday in Khartoum."Over the same period, the number of under-nourished rose from 200 million to 224 million in Africa. This is a cause of concern for all of us."The rise in malnutrition and food insecurity was related to climate changes and disasters like floods, droughts and crop failures, Tijani later told AFP on the sidelines of the forum.He said conflicts in countries like Somalia, South Sudan and the Central African Republic further increased food insecurity."When you look at those conflicts, it has also brought challenges because even when food is available it is not affordable and it cannot reach those conflict areas."UN officials have warned that growing food insecurity was displacing more and more people across the region, with food needs being the main cause in countries such as South Sudan.KEEP UPDATED on the latest news from around the continent by subscribing to our FREE newsletter, Hello Africa.FOLLOW News24 Africa on Twitter and Facebook. About one million South Sudanese have crossed borders to become refugees as they flee violence in the world's youngest country formed in 2011.Soon after its secession from the north, South Sudan descended into war in December 2013 when President Salva Kiir accused his former deputy Riek Machar of plotting a coup.On a positive note, Tijani said Africa's economy was improving and its food and agriculture market was estimated to reach one trillion dollars by 2030.This created opportunities for new investments.Hundreds of delegates from across Africa will be attending the five-day conference in the Sudanese capital to discuss efforts to eradicate hunger and food insecurity in Africa.