UN Special Envoy for Yemen Hans Grundberg announced on Sunday that no agreement has been reached to renew the expired truce between the Yemeni warring parties.

"The UN Special Envoy regrets that an agreement has not been reached today, as an extended and expanded truce would provide additional critical benefits to the population," his office said in a statement.

"I appreciate the position of the Government of Yemen on engaging positively with my proposal. I will continue to work with both sides to try and find solutions," Grundberg was quoted as saying.

He noted that the proposal submitted to the warring parties on Saturday includes the extension of the truce for another six months, salary and pension payment for civil servants, and the opening of specific roads into the besieged government-controlled city of Taiz and other provinces.

It also includes additional destinations for flights to and from the Houthi-controlled airport in the Yemeni capital of Sanaa, and unhindered entry of fuel ships into the Red Sea port of Hodeidah held by the Houthis.

Thousands of civil servants in the Houthi-controlled cities have not been paid for more than seven years.

The Yemeni government has agreed to the UN proposal, welcoming the United Nations' efforts to end the civil war in Yemen, according to the state media outlets.

Yemen's Minister of Foreign Affairs Ahmed Awad Bin Mubarak told Xinhua earlier in the day that his government already sent Grundberg its approval for the extension agreement.

Although the Saturday proposal has reflected the main terms that the Houthis have been demanding since the truce began on April 2, the Houthis have yet to make a statement on why they rejected the UN proposal, and claimed that the government side did not remain committed to the previous six months of the truce, threatening to launch cross-border missile attacks on the oil facilities in Saudi Arabia and the United Arab Emirates.

"The (Houthi) Armed Forces give the oil companies operating in the UAE and Saudi Arabia an opportunity to arrange their status and leave," Houthi military spokesman Yehya Sarea said in a statement aired by the Houthi-run al-Masirah TV minutes after Grundberg announces the truce extension failure on the UN website.

"The truce has reached a dead end," the Houthi military spokesman added.

Breakthroughs in the past six months of the truce include the resumption of commercial flights to and from the Sanaa airport and the entry of fuel ships into the port of Hodeidah. However, the siege on Taiz city has not been lifted yet.

On April 2, the Yemeni government and the Houthis agreed upon a two-month truce brokered by the United Nations. The truce was later renewed twice through Oct. 2.

Yemen has been mired in a civil war since late 2014 when the Iran-backed Houthis seized control of several northern cities and forced the Saudi-backed Yemeni government out of the capital Sanaa.

-Agencies