LONDON: The World Food Programme (WFP) is considering suspending aid delivery in the areas under the control of Yemen's Houthi group because of fighting, insecurity and interference it its work, the agency said on Monday.

"Humanitarian workers in Yemen are being denied access to the hungry, aid convoys have been blocked, and local authorities have interfered with food distribution," the WFP said in a statement. "This has to stop."

The highly unusual threat from the UN agency, which is feeding more than 10 million people across Yemen, reflected what it said were "obstacles that are being put in our way".

"We face daily challenges due to the unrelenting fighting and insecurity in Yemen. And yet, our greatest challenge does not come from the guns, that are yet to fall silent in this conflict - instead, it is the obstructive and uncooperative role of some of the Houthi leaders in areas under their control."

Negotiations with Houthi leaders to open up access to hungry people had not yet brought tangible results, WFP said, although some had made positive commitments.

"Unfortunately, they (Houthi leaders) are being let down by other Houthi leaders who have broken assurances they gave us on stopping food diversions and finally agreeing to a beneficiary identification and biometric registration exercise."

WFP's threat of a partial pullout comes after fighting around Hodeidah marred an apparent diplomatic breakthrough by U.N. envoy Martin Griffiths, who got the Iranian-aligned Houthis to agree a unilateral withdrawal of their forces from Hodeidah and two other ports earlier this month.