The UN High Commissioner for Refugees (UNHCR), has appealed for more countries to help Yemen cope with an influx of refugees from Somalia.
A senior European Union official accompanying him on a trip here pledged the bloc would send millions of dollars more to the country.
"I want to strongly appeal to the international community to increase support to Yemen and share [with] it the same generosity it has shown to the [African] refugees," Mr Guterres said here yesterday.
"I feel a certain frustration when I see that the relationship with Yemen is focused on security and the fight on terrorism … [since] the best way to ensure stability is to create job opportunities, fight poverty."
Mr Guterres and Kristalina Georgieva, the EU Commissioner for International Cooperation, Humanitarian Aid and Crisis Response, arrived in Yemen on Thursday to get a first-hand look at the situations of internally displaced Yemenis in the north of the country and refugees crossing the Gulf of Aden and the Red Sea from Somalia.
About 300,000 people have been displaced since 2004 because of the intermittent conflict between rebels and the government in that country.
The UNHCR estimates there are currently more than 170,000 refugees, mainly from Somalia, while the Yemeni government puts the figure at between 700,000 and one million.
Ms Georgieva pledged the EU Commission would increase its humanitarian aid to Yemen, which now stands at US$14 million (Dh51m), by 50 per cent.
Mr Guterres and Ms Georgieva later became the highest-ranking UN and EU officials to visit Yemen's troubled northern Sa'ada province, and welcomed commitments by both the government and Houthi rebels to grant full access and safe passage to international humanitarian workers.
Meanwhile, in Sana'a yesterday, dozens of people staged a demonstration in front of the cabinet building to demand the release of 92 Yemeni detainees held at the US-run Guantanamo military base prison in Cuba.
The protesters, including families of Guantanamo inmates and human-rights activists, demanded the Yemeni and US governments free inmates who have been in the jail since 2001.
"We are here today to demand the release of our brothers in Guantanamo and pressure the Yemeni government to increase its demands to Washington to set them free," said Sami al Hajj, a Sudanese former cameraman for the Al Jazeera satellite television channel who was detained by the Americans and sent to the Guantanamo facility.
Mr al Hajj, who has been recently campaigning in Paris, Khartoum, and London for the release of those still in jail urged Barack Obama, the US president, to respect his promise to close the jail.
"We are here to tell Obama to respect his promise to close Guantanamo. He has promised change but we found nothing but cheating.
Those are innocent and were even acquitted by the US courts," Mr al Hajj said.
The protesters, who carried photographs of the inmates, also appealed to Yemen's President Ali Abdullah Saleh to take action.
The Obama administration suspended plans to repatriate Yemeni Guantanamo detainees after the failed Christmas Day attack on a US airliner over Detroit in December 2009.
Mr Obama announced last January that he was suspending the transfers of additional detainees to Yemen from Guantanamo, even while saying he remained committed to his plan, now delayed, to close the American prison in Cuba.