United Nations, New York - Houthi rebel and Yemeni government representatives did not meet face-to-face in the port city of Hodeidah over the past week despite a recently-inked peace plan, United Nations spokesman Stephane Dujarric said on Monday.

The UN's Patrick Cammaert has been forced to "shuttle" between the rebel and government sides, who had twice met together under the so-called Redeployment Coordination Committee (RDC) before those direct talks broke down, the UN said.

Their refusal to sit together highlights the difficulty in implementing the UN-brokered deal, reached between the government and rebels on December 13 in Rimbo, Sweden.

Dujarric said that Cammaert's meetings were aimed at finding a "mutually acceptable way forward for the redeployment of forces from the three ports and critical parts of the city associated with humanitarian facilities".

Under the terms of the Rimbo deal, the Houthis were expected to hand over control of the ports of Hodeidah, Saleef and Ras Isa to local security forces in liaison with Cammaert and envoys from the Saudi-backed government. However, both sides have disagreed over the wording of the agreement.

Not going 'smoothly'

Although a ceasefire in Hodeidah has largely stuck, each side has accused the other of violating the truce. Near-daily missile fire and automatic gunfire can reportedly be heard by the thousands of civilians who still reside in the city.

Elsewhere in Yemen, the Iran-aligned Houthis threatened to continue ongoing drone attacks, after a deadly strike last week on a Yemeni government military parade, stoking tensions between the warring parties amid shaky UN peace efforts.

According to Dujarric, the Hodeidah talks had faced setbacks and could not be described as going "smoothly", but he noted there were still hopes of re-opening the Red Sea port city's vital transit routes for aid and other supplies.

"While projected timelines have slipped, recent discussions have been constructive," Dujarric told reporters in New York.

Cammaert "continues to encourage the parties to resume the joint meetings in order to finalise a mutually agreed redeployment plan. Currently, plans are being discussed on how to facilitate humanitarian operations."

The UN Security Council is expected to vote later this week on a UK-drafted resolution to expand Cammaert's team to include 75 UN monitors - for an initial period of six months - to oversee the Hodeidah ceasefire and troop redeployment.

Last month's ceasefire came after the Saudi-UAE-backed pro-government forces launched a major offensive in June aimed at driving Houthi rebels out of the city.

The Red Sea port is the key transit point for food, medicine and other supplies to Yemen, where 14 million Yemenis are on the brink of famine, according to UN figures.

Yemen has been wracked by violence since 2014 when the Houthis stormed south from their stronghold of Saada and overran much of the country, including the capital Sanaa where they toppled Yemeni President Abd-Rabbu Mansour Hadi's unpopular government.

Fighting escalated in 2015 when Saudi Arabia and the UAE, who accuse the Houthis of being Iranian proxies, launched a military coalition that began air attacks against Houthi positions in an attempt to reinstate Hadi.

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