German and Omani foreign ministers called for a cease-fire in Yemen on Tuesday as a UN special envoy and a senior Iranian diplomat also arrived in the German capital of Berlin for talks to end fighting. German Foreign Minister Frank-Walter Steinmeier criticized the recent Saudi-led airstrikes on the Houthi-occupied cities and urged for a cease-fire to ease civilian suffering. "The recent bombings of ports and road blockades in Yemen have made it much more difficult for international humanitarian organizations to deliver aid to civilians," Steinmeier said at a press conference with his Omani counterpart Yusuf bin Alawi bin Abdullah. Fractious Yemen has remained in turmoil since last September, when Houthi militiamen overran capital Sanaa, from which they have since extended their influence southwards to other parts of the country. Since March, Saudi Arabia and its Arab allies are carrying out extensive air campaign targeting Houthi positions across Yemen. The conflict has made almost 80 percent of the population dependent on humanitarian aid. Oman's diplomatic efforts Steinmeier backed Oman's diplomatic efforts to help the UN broker a political solution to the conflict, and said special envoy to Yemen, Ismail Ould Cheikh Ahmed, would also have talks in Berlin later Tuesday. "We have agreed today to remain active in appealing partners in the region towards reaching for at least a cease-fire in the very near future," Steinmeier said. Bin Alawi expressed grave concerns for the ongoing fighting in neighboring Yemen and vowed to continue diplomatic efforts. "We hope that our Yemeni brothers, despite all their disagreements, will grasp the opportunity to talk to each other and stop the bloodshed," he said. Iranian senior diplomat in Berlin As Germany and Oman stepped up efforts for a cease-fire in Yemen, Iranian Deputy Foreign Minister Hossein Amir-Abdollahian arrived in Berlin for talks on Yemen and Syria. Diplomatic sources confirmed that Amir-Abdollahian would hold high-level talks with German officials Tuesday and Wednesday, and would also meet Markus Ederer, state secretary of the German Foreign Ministry. Ederer made various visits to Iran and Saudi Arabia in the last couple of months to facilitate a cease-fire and a political solution to the conflict in Yemen. Regional powers Iran and Saudi Arabia accuse each other for aggression in Yemen. Riyadh says its air campaign comes in response to appeals by Yemeni President Abd Rabbuh Mansour Hadi for military intervention against the Houthis. Hadi, who is backed by gulf states, fled to Riyadh in March after Houthi forces attacked his residence in Yemen's southern port city of Aden. Some gulf states accuse Iran of supporting Yemen's Houthi insurgency.