On Monday, Secretary-General Ban Ki-moon called for an inquiry after an Arab coalition airstrike in Yemen seriously damaged a UN Development Program office and injured a guard in the city of Aden. Farhan Haq, a spokesman for the United Nations, said that Ban also called for a return to peace talks.

"The secretary-general urges a full investigation into this incident and that anyone found to be responsible for any breaches be held to account," UN spokesman Farhan Haq said on Monday.

Saudi Arabia and its Gulf allies have demanded that the Houthi rebels pull back from territory seized in their offensive and that President Abed Rabbo Mansour Hadi return to power. And since March, they have backed those demands with airstrikes.

'End the fighting'

The United Nations has also launched a fundraising drive for Yemen. Two weeks ago, Ban had asked all sides to end fighting during Ramadan. A week of UN-brokered talks in Geneva earlier this month failed to narrow differences between the sides.

"The secretary-general strongly believes that this incident only underscores the imperative that all the parties to the conflict must end the fighting and return to the negotiation table as the only possible way to achieve a durable peace in Yemen," Haq told reporters on Monday.

Earlier in June, the "Islamic State" announced that it had gained a foothold in Yemen, claiming responsibility for a string of bombings.

mkg/msh (Reuters, AFP)