Five years of civil war has turned Yemen -- the poorest Arab nation on the Arabian Peninsula -- into the world's worst humanitarian crisis. An estimated 100,000 people have been killed during the conflict.

Yemen is home to 24 million people. About 80 percent of the population depends on food and humanitarian aid to survive.

Yemen's warring groups have welcomed a United Nations call for an immediate end to the conflict. But Middle East experts believe that such calls will not stop the fighting.

A Saudi Arabian-led coalition launched a military offensive against Iranian-supported Houthi rebels five years ago. The coalition’s members wanted to re-establish Yemen’s ousted government, under President Abed Rabbo Mansour Hadi.

Rights groups have accused both the Saudi-led forces and the rebels of rights violations against civilians, as well as war crimes.

Yemen expert Helen Lackner says the conflict appears to have no end. She told VOA, "These policymakers, as far as the Yemenis are concerned, are actively promoting the fighting…they don't care one bit about the millions who are suffering."

Lackner added that at the end of 2019, the fighting appeared to be slowing. But two major agreements failed to move forward. The United Nations-supported Stockholm agreement was supposed to end the coalition offensive on the port of Hodeida. The Riyadh agreement was to solve the crisis between Hadi's government and STC.

But Lackner notes there has been a serious increase in fighting since January, especially in Yemen’s south. She adds that a major Houthi offensive also threatens other parts of the country that were once said to be more secure.

Cinzia Bianco is watching events in Yemen for the European Council on Foreign Relations. She told VOA she expects the situation in Yemen to worsen if the Houthis continue their offensive toward the center of Marib province.

Bianco predicts rising tensions in two separate areas: “one...in the north, and the other in the south, along the Red Sea coast.”