GENEVA - The United Nations raised more than $2 billion on Tuesday to help civilians in Yemen, with half the funds pledged by governments that are bombarding the war-ravaged country.

UN secretary-general Antonio Guterres hailed the donor conference in Geneva as a "remarkable success". The target for the 2018 Yemen humanitarian appeal was set at $2.96 billion (2.4 billion euros). Guterres told reporters that in addition to the $2 billion already committed, multiple countries had promised more donations in the coming months, leaving him "optimistic that we will be able to reach the level that corresponds to the needs".

Last year's Yemen appeal for $2.5b, which was 73 percent funded, but the needs have intensified in a country battered since 2015 by a Saudi-led military offensive aimed at repelling Iran-backed Huthi rebels who control the capital.

The UN has labelled Yemen "the world's worst humanitarian crisis" and said that three-quarters of its population - around 22 million people - need some form of aid.

Saudi Arabia and its allies have repeatedly been accused of hitting civilians targets including hospitals and markets in their three-year campaign against the Huthis.

The kingdom and its coalition partner, the United Arab Emirates, were also the largest donors at Tuesday's conference, jointly pledging $1 billion in humanitarian relief, according to figures provided by the UN. Asked if he saw a contradiction in the Saudi stance towards Yemen, Guterres said a country's humanitarian commitments and military actions should be kept separate.

"We all know that there is a war. We all know who the parties (are) to the war but the two things need to be seen separately," the UN chief told reporters.

"Independent of the fact that there is a war, there are humanitarian obligations that are assumed by countries," he said.

"The countries that are also party to the conflict were party to these international efforts to support the people of Yemen."

Guterres underscored that the only way to ensure that Yemen donor conferences do not continue year after year is for the sides to negotiate a peace deal.

"There was never a humanitarian solution for any humanitarian crisis," he said. "The solution has always been political"

The UN's Yemen envoy, Martin Griffiths, has recently visited Riyadh and Sanaa in hopes of revitalising sputtering peace talks.

"I believe there is an opportunity and that opportunity must be seized," Guterres said, explaining that Griffiths was "encouraged" by his trip and sees a window for further talks.

According to the UN, 8.4 million people are on the verge of famine in Yemen, where food imports are essential to sustain the population.

The Saudi-led coalition shut down the country's land, sea and air borders last year in response to a missile attack by the Huthis that was intercepted near Riyadh.

While the coalition has eased the blockade, restrictions on deliveries persist.

"Humanitarians must be able to reach the people who need help the most, without conditions," Guterres said.

"All ports must remain open to humanitarian and commercial cargo, the medicines, food and the fuel needed to deliver them," he added, emphasising the need for "unrestricted access" to the country and within it.

About 10,000 Yemenis have been killed and 53,000 wounded since the start of the coalition intervention in Yemen.