A ceasefire committee will be formed in Yemen following UN sponsored peace-talks but mutual distrust prevented any real progress being made. 

The talks, which ended yesterday after six days, were threatened as fresh fighting broke out hours before a ceasefire was due to commence. The eight-month conflict has now killed thousands of people and caused a major humanitarian disaster in inpoverished Yemen.

The ceasefire committee will be headed by a Lebanese army general and consist of representatives from the Saudi-backed government of Yemen's President Abd-Rabbu Mansour Hadi and from the rival Houthi movement, which is allied to Iran.

But after the apparent breakthrough on the committee, Saturday's round of talks did not yield more results.

Face-to-face talks between Hadi's government and the Houthi rebel group have not occurred since Wednesday evening after the Houthis rejected demands for the release of detained senior officials, including Yemen's defence minister and Hadi's brother, said sources close to the talks.

The UN special envoy, Ismail Ould Cheikh Ahmed, is shuttling between the two sides to try and bridge differences.

Disagreements were over a proposed prisoner exchange and the opening of a humanitarian corridor to the war-torn city of Taiz, said the sources.

In addition, a rare one-week truce meant to facilitate the negotiations was compromised on Saturday afternoon as clashes broke out between Houthi fighters and Saudi troops along the Yemeni-Saudi border.

Both sides accuse each other of violating the ceasefire.

Saudi's Civil Defence Force said on Twitter that a rocket fired from Yemen killed two Saudi workers and injured a civilian in the Saudi border city of Najran.

The United Nations Special Envoy for Yemen voiced deep concern at "numerous reports of violations of the cessation of hostilities", a UN statement said on Friday.

Yemen, which was swept by mass Arab Spring-inspired protests in 2011, was this year plunged into war after the Houthis overthrew the central government, prompting Saudi Arabia and other Arab states in March to launch a bombing campaign.

Troops loyal to Hadi seized an important northwestern city and a military base from Houthis on Friday who still control the capital Sanaa, said residents and tribal sources.

Planes and gunboats from a Saudi-led military coalition also bombarded targets in northern Yemen, said residents.

The Houthis say they are ready to free the prisoners once a permanent ceasefire is agreed, another source close to the talks told Reuters.

Hospital sources said on Saturday that limited medical aid had reached a few Houthi-controlled districts in the central city of Taiz, one of the worst-affected cities.

Additional reporting from Reuters.