A Saudi-led coalition has resumed air strikes against Houthi rebels in Yemen after a five-day ceasefire ended, Yemeni officials and witnesses say.
Aircraft targeted rebel positions in the southern city of Aden overnight, despite a UN call for the truce to be extended to allow in more aid.
Yemeni parties are in negotiations in Saudi Arabia on how to end the crisis.
But the rebels, who reject the return of exiled President Abdrabbuh Mansour Hadi, are boycotting the talks.
Mr Hadi fled the country at the end of March after rebel forces and allied army units loyal to ousted former president Ali Abdullah Saleh advanced on Aden.
He had taken refuge in the city the previous month after the Houthis consolidated their control of Sanaa and placed him under effective house arrest.
“Avoid airports, infrastructure”
The new UN envoy to Yemen opened talks with the country’s various factions in the Saudi capital on Sunday urging all sides to “renew their commitment to this truce for five more days at least”.
Ismail Ould Cheikh Ahmed also said they should “refrain from any action that disturbs the peace of airports, main areas and the infrastructure of transport”.
Despite the appeal, coalition air strikes reportedly resumed after the ceasefire expired at 23:00 (20:00 GMT) on Sunday, with warplanes bombing the rebel-held presidential palace in Aden on Monday, as well as the city’s international airport.
On Monday morning, Yemen’s foreign minister told Reuters news agency that his government would not consider a new ceasefire offer, blaming it on the Houthis who he said had violated the terms of the truce.
“That’s what we said before – that if they start again, we will start again,” Riad Yassin said.
But, he continued, the air strikes would avoid the main airport in the capital Sanaa and the western Red Sea port of Hudaydah to allow aid to be brought in.
The coalition air campaign, which began on 26 March, has so far failed to achieve its stated aim of restoring President Hadi.
Aid agency appeal
Despite some clashes the five-day ceasefire largely held, allowing aid agencies to deliver desperately-needed food, water, medicine and fuel. However, the agencies said they were only able to reach a small number of those in need.
Unicef’s representative in Sanaa said on Sunday that while it was able to deliver aid to affected people across the country, “humanitarian assistance cannot replace the needs of 26 million people who have been cut off from a regular supply of commercial imports of food and fuel”.
“Hundreds of adults and children have already died during this conflict,” Julien Harneis said, “many of whom could have been saved had we got supplies to them on time”.
Iran has sent a cargo ship carrying humanitarian aid, due to arrive in Hudaydah on Thursday, state media report.
More than 1,800 people have been killed in air strikes and fighting on the ground since the Saudi-led military intervention began, with up to 545,700 people displaced by the violence, according to the latest UN figures.