Kuwait City (AFP) - Crucial talks between Yemen's government and rebels were delayed Monday after the insurgents failed to show up, prompting UN concern over the fate of peace efforts for the war-torn country.
The talks in Kuwait aim to end to more than 13 months of fighting that has devastated already-impoverished Yemen.
A week-old ceasefire meant to lay the groundwork for the talks has been repeatedly breached, with both sides trading blame.
Representatives of the internationally recognised government as well as the Iran-backed Huthi rebels and their allies -- loyalists of former president Ali Abdullah Saleh -- had been due to gather Monday morning in Kuwait for the negotiations.
But while a government delegation led by Yemeni Foreign Minister Abdulmalek al-Mikhlafi was in Kuwait, the rebel delegation remained in Yemen, protesting over alleged Saudi truce violations.
"Our presence in Kuwait requires a total halt to (Saudi) aggression," said Huthi rebel leader Mohamed Ali al-Huthi, quoted on the website sabanews.net, demanding "a guarantee that (coalition) warplanes will no longer violate Yemen's sovereignty".
Saudi Arabia is leading a military coalition of Arab Sunni states which has been supporting pro-government forces with air strikes, weapons and troops since March last year.
Speaking from Yemen's rebel-held capital, a source from the Huthi political bureau confirmed to AFP that the rebels, expected in Kuwait alongside representatives from Saleh's General People's Congress party, had not left Sanaa.
A statement from the government delegation in Kuwait accused the rebels of "irresponsible behaviour", and called for the international community to show "firmness in the face of their contempt for the peace efforts".
"Due to developments over the last few hours, the start of the Yemeni-Yemeni peace negotiations scheduled to begin today... will be delayed," UN envoy Ismail Ould Cheikh Ahmed said in a statement, without specifying when they might take place.
"The next few hours are crucial," he said, calling on all parties to "take their responsibilities seriously and agree on comprehensive solutions".
- 'Opportunity to save lives' -
Saudi Arabia launched the intervention after the rebels, a Shiite minority group that has long complained of marginalisation, descended from their northern stronghold in Yemen to seize control of Sanaa in 2014.
As they advanced into other areas, President Abedrabbo Mansour Hadi and other officials fled first to the main southern city of Aden and eventually to Riyadh.
The loyalists have since managed to reclaim large parts of the south, establishing a temporary capital in Aden, but have failed to dislodge the Huthis from Sanaa and other key areas.
Before the UN announcement of a delay, the Saudi government voiced hope for "the success of consultations" in Kuwait, in a statement published on the official Saudi Press Agency.
The UN's Ould Cheikh Ahmed urged the Huthis and their allies not to "miss this opportunity that could save Yemen the loss of more lives".
He had earlier expressed hopes for the talks, telling the UN Security Council on Friday that Yemen has "never been so close to peace".
The ceasefire, in place since April 11, has been repeatedly violated but the rebels, the government and the Saudi-led coalition have avoided talk of it collapsing, as happened with three earlier truces.
The situation across Yemen was relatively calm on Monday despite skirmishes in several areas, local sources said.
Military sources said a rebel attack killed three soldiers in the eastern Marib province, including a colonel.
There was continued fighting in Nahm, northeast of Sanaa, sources said, and sporadic clashes in the southwestern Taez province.
In Aden, thousands of supporters of the Southern Movement demonstrated for the south's secession, in the second such rally in as many days.
Previous attempts at peace talks -- including a failed round in January -- have been unable to stop Yemen's conflict, which the United Nations says has killed more than 6,400 people and forced almost 2.8 million from their homes.
Among the issues meant to be tackled in Kuwait are security arrangements, the withdrawal of militias and armed groups, the handover of heavy weapons and the release of detainees.
Jihadists including from Al-Qaeda in the Arabian Peninsula (AQAP), the powerful Yemeni branch of the extremist network, have exploited the conflict to seize territory and gain influence.