Saudi-led airstrikes killed at least seven people in
Yemen is more than 15 months into a war involving a Saudi-led Arab coalition that intervened to prevent Iranian-allied Houthis from overthrowing the government.
Residents confirmed that five people died in the attack but did not say if they were civilians or armed members of the Houthis, a movement from the Zaydi branch of Shi'ite Islam.
In southern Yemen, residents said two women died in an air strike on the home of a merchant in the Qubaita district, located between the Taiz and Lahej provinces.
There was no immediate comment from the coalition on the reports.
Ban hopes to push the combatants to make concessions. In a message to Yemeni negotiators from the Saudi-backed government on one side and the Houthis on the other, he said they must try to learn from the example of Colombian rebels and the government who signed a deal last week in Cuba after decades of war.
"I urge both delegations to avoid driving the situation to a crisis, and work responsibly and with flexibility for a comprehensive solution that would end the conflict," he wrote.
The Yemen war has killed more than 6,400 people and caused a severe humanitarian crisis in a country that was already one of the poorest in the world. Yemen shares a long border with the world's top oil exporter, Saudi Arabia.
Officials say the talks have been going in circles: The Houthis demand an agreement on the fate of President Abd-Rabbu Mansour Hadi and the formation of a broad government that would include them before any withdrawal from cities they seized.
The Yemeni government insists that any new government would only be formed after the Houthis hand over their weapons and retreat to their home area in Saada province in the north.