Efforts to <a href="https://www.thenationalnews.com/gulf-news/2022/05/23/yemen-government-upbeat-on-truce-extension-after-houthis-say-not-opposed/" target="_blank">extend a truce</a> between Yemen’s government and the Houthi rebels appear to be “in trouble”, the US envoy to the UN Linda Thomas-Greenfield said on Tuesday. If the truce — set to expire this week — is not extended, Yemen could be plunged back into bloody civil war. Ms Thomas-Greenfield said Washington was concerned about an apparent breakdown in talks aimed at extending the two-month ceasefire, which took effect on April 2 and has largely held, bringing rare moments of calm to Yemen's long-suffering population. “The fact that these talks seem to have come — they haven't ended yet, but seem to be a bit in trouble — is troublesome to us,” Ms Thomas-Greenfield told reporters in New York. “We encourage the parties on both sides to continue those efforts and find a peaceful way to provide needed humanitarian assistance to the people of Yemen.” Her comments came amid a flurry of diplomacy to stop Yemen from sliding back into all-out fighting between the Houthis, Yemen’s internationally recognised government and the Saudi Arabia-led coalition seeking to restore it to power. US Secretary of State Antony <a href="https://www.thenationalnews.com/gulf-news/saudi-arabia/2022/05/31/uss-antony-blinken-discusses-efforts-to-extend-yemen-truce-with-saudi-counterpart/" target="_blank">Blinken has spoken with Saudi Foreign Minister Prince Faisal bin Farhan</a> about the truce, while UN Secretary General Antonio Guterres urged Gen Rashad Al Alimi, head of Yemen's Presidential Leadership Council, to work for its renewal. In that call, the UN chief “underscored the critical role of the truce in addressing some of the most immediate humanitarian and economic needs to alleviate the suffering of the Yemeni people”, UN spokesman Stephane Dujarric told reporters on Tuesday. Talks to extend the truce have been dogged by a <a href="https://www.thenationalnews.com/mena/2022/05/28/yemen-rivals-in-talks-to-reopen-roads-around-besieged-taez/" target="_blank">Houthi ground blockade around the government-held city of Taez</a>, Yemen's third largest. The truce deal featured the reopening of roads around Taez, recommencing flights to the rebel-held capital Sanaa and other goals. Save The Children, Oxfam, the Norwegian Refugee Council and other aid agencies operating in Yemen on Tuesday urged the warring parties to extend the truce, which has eased the suffering of millions. “We have seen the positive humanitarian impacts of the truce,” said the joint statement from more than 30 charities. “We … urge you to extend the truce agreement, build further on the gains you have made possible over the past two months and work towards peace for the people of Yemen.” Earlier this month, the NRC said the number of civilian casualties in Yemen had more than halved since the truce — the country’s first nationwide ceasefire agreement since 2016 — came into effect. Under the truce, more than 1,000 passengers have <a href="https://www.thenationalnews.com/mena/2022/05/15/yemen-restart-of-flights-from-sanaa-expected-on-monday/" target="_blank">flown between Sanaa and Jordan</a>, and a route to Egypt is expected to begin soon. Flights have given hundreds of sick Yemenis access to “life-saving medical treatment” abroad, the aid groups said. The Houthis seized control of Sanaa in 2014, prompting a Saudi-led military intervention to support the government the following year. Hundreds of thousands of people have died in the war and the country is on the <a href="https://www.thenationalnews.com/gulf-news/2022/03/15/yemens-famine-to-increase-five-fold-this-year-report-warns/" target="_blank">brink of famine</a>.