A Yemeni soldier, loyal to the Shiite Houthi movement, walks next to humanitarian aid supplies given by the Russian humanitarian relief mission in a camp on the outskirts of the capital Sanaa on March 16, 2017.
A Yemeni soldier, loyal to the Shiite Houthi movement, walks next to humanitarian aid supplies given by the Russian humanitarian relief mission in a camp on the outskirts of the capital Sanaa on March 16, 2017.

UNITED NATIONS - The World Food Program warned Monday that it may have to suspend the distribution of food aid in Houthi rebel-controlled areas of Yemen, if the group does not stop obstructing its work.

In a statement, the United Nations food agency said humanitarian workers are being denied access to the hungry, aid convoys have been blocked and local authorities have interfered with food distribution. The agency also accuses the rebels of interfering with the independent selection of people to receive the aid and its plans to implement a biometric registration system. 

"Our greatest challenge does not come from the guns that are yet to fall silent in this conflict," WFP said in its statement. "Instead, it is the obstructive and uncooperative role of some of the Houthi leaders in areas under their control." 

The U.N.'s humanitarian operation in Yemen is its largest in the world. It has appealed for $4.2 billion to fund aid programs there this year. 

The world body says 14 million people are in acute need and another 10 million require some form of humanitarian assistance or protection. Millions of them live in Houthi-controlled areas in the west and northwest of the country.

"Already, many are not being reached because of the obstacles that are being put in our way," WFP said. "If we are not given the access and freedom to decide who gets this vital assistance, then we will have to take the hard decision of implementing a phased suspension of our operations in Houthi controlled areas."

The food agency said that would be an option of "last resort" and hopes that "good sense will prevail." 

A Saudi Arabian-led coalition began bombing Iranian-aligned Houthi rebels in support of Yemen's government in March 2015. Since then, the U.N. estimates more than 10,000 people have been killed, mostly due to coalition airstrikes.