SANAA, Sept. 6 (Xinhua) - Yemen's Houthi rebels on Thursday said their delegation in the capital Sanaa was prevented from flying to Geneva to attend United Nations-sponsored peace talks, the group-controlled Saba news agency reported.

"The forces of the aggression (Saudi-led coalition) have still been refusing to give required authorizations to an Omani plane in the capital Sanaa to transfer the (Houthi) delegation to Geneva," the Houthis said in a statement.

In the statement, the Houthis "blamed the United Nations for failing to secure the authorizations from the coalition which controls Yemen's airspace."

However, Saudi-owned Al-Ekhbariyah television cited Colonel Turki al-Maliki, the spokesman of the Saudi-led coalition, as saying that "the coalition had given authorization to the plane of Houthi rebel delegation based on an official request from the United Nations."

"However, the United Nations on Wednesday sent another request to the coalition, demanding the coalition to cancel the authorization of the Houthi plane," he said.

Also on Thursday, the coalition-backed Yemeni government delegation already in Geneva gave the Houthis a 24-hour deadline to show up in the peace talks, according to pro-government media outlets.

Hours later, the UN envoy for Yemen Martin Griffiths already in Geneva told reporters that "no meeting for Yemen's peace talks tomorrow (Friday)." Griffiths gave no further details.

The Geneva meeting was scheduled to be held on Thursday, Sept. 6, then was adjourned until Friday.

On Wednesday, delegation of the internationally-recognized Yemeni government arrived in Switzerland's Geneva to participate in a new round of talks sponsored by the United Nations to end a four-year-old military conflict with the Iranian-backed Houthi rebels.

Also on Wednesday, UN envoy Griffiths told reporters in Geneva that "the Houthis want to attend, and he will make sure they will."

"The UN and others are working to ensure the timely arrival of the Houthi delegation," Griffiths said.

The last UN-backed peace negotiations for Yemen were held in 2016 in Kuwait, which continued for several months in the Gulf country but no constructive results had been reached due to serious differences between the rival parties.

Yemen has been locked into a civil war since the Houthi rebels overran much of the country militarily and seized all northern provinces, including capital Sanaa, in 2014.

Saudi Arabia is leading an Arab military coalition that intervened in Yemen in 2015 to support the government of President Abd-Rabbu Mansour Hadi after the Houthi rebels forced him into exile.

The United Nations and other organizations have listed Yemen as the world's number one humanitarian crisis, with an estimated eight million of Yemenis remaining precariously close to famine.

According to a latest statement by the World Food Programme, intensified conflict is making the humanitarian situation in the country worse, particularly in Hodeidah, the key port which is a lifeline for millions in northwestern Yemen.