Oman on Tuesday joined a growing list of countries in the region and further afield to welcome Saudi Arabia's initiative to end the Yemen war. Capitals around the world urged all sides to work towards ending the six-year conflict. Muscat is a crucial mediator in the Yemeni conflict, providing aircraft to take Houthi rebel negotiators to peace talks, securing prisoner exchanges and laying on humanitarian flights. “The sultanate will work with the kingdom [of Saudi Arabia], the UN, Yemen and all the parties concerned with a view to achieving a political settlement to return … security and stability,” the Oman state-run news agency reported. On Monday, Saudi Arabia proposed a nationwide ceasefire, the reopening of Sanaa International Airport to some destinations, the resumption of talks between Yemen's warring sides, allowing additional fuel and commodities to enter Hodeidah port and supporting reconstruction and aid efforts in the country. While the plan got the backing of Washington, Europe and – crucially – the internationally recognised Yemeni government, the Iranian-backed Houthi rebels said it did not appear to go far enough. The UN said Saudi Arabia's plans aligned with its peace initiative, urging all sides in the conflict to work together to end the war. “There is no doubt that every effort must be made to end the conflict in Yemen and address the suffering of the Yemeni people, and the UN looks forward to continuing its work with the parties to achieve this goal,” Farhan Haq, the UN’s Secretary General's deputy spokesperson, said. Mr Haq said UN envoy to Yemen Martin Griffith would follow up with all the parties, including the Houthis. The US welcomed the commitment of Saudi Arabia and Yemeni President Abdrabu Mansur Hadi's administration to a ceasefire and negotiations, deputy State Department spokeswoman Jalina Porter said. The announcement made by the kingdom is "one step in the right direction" and all parties should "commit seriously" to an immediate ceasefire and engage in negotiations under the auspices of the UN, Ms Porter said. Britain's Foreign Secretary Dominic Raab said the Houthi rebels must work together with their Saudi opponents on ending the conflict. “I welcome today’s announcement by Saudi Arabia on Yemen. A nationwide ceasefire and action to ease humanitarian access restriction are essential. The Houthis must now match the steps towards peace and an end to the suffering of the Yemeni people,” Mr Raab wrote on Twitter. The EU said it saw the announcement as a positive step in the process towards peace. “The EU encourages all parties to engage without delay with the UN special envoy so that a ceasefire is immediately declared and an inclusive political process under the auspices of the UN is quickly launched,” it said. Only a comprehensive and inclusive political agreement remains will be the long-term solution to ending the war in Yemen, said the EU. The plan received regional backing as well. “The Saudi initiative to end the crisis in Yemen and reach a comprehensive political agreement represents a real opportunity to end the suffering of the brotherly Yemeni people,” said Dr Anwar Gargash, diplomatic adviser to UAE President Sheikh Khalifa. “Saudi’s good efforts are based on concern for the stability and future of Yemen. The time has come for the guns to stop and heed the sincere invitation from Riyadh.” Egypt said it appreciated the kingdom’s "sincere efforts" to end the crisis, calling on all sides to co-operate. “Egypt is calling on all Yemeni parties to respond to the Saudi initiative to end the bloodshed and support efforts to bring peace to Yemen,” the foreign ministry said. Qatar said it welcomes all initiatives and efforts aimed at ending the war and putting an end to the "tragedy of the Yemeni people". The war began when the Iran-backed Houthi rebels took over the capital in a 2015 coup, leading Mr Hadi's internationally recognised government to call on allies to assist. The Saudi-led coalition entered the conflict months later. UN efforts to mediate an end to the conflict looked hopeful in December 2018, with an agreement reached in Stockholm for ceasefires in the port city of Hodeidah and two other ports, Salif and Ras Issa, and a successful prisoner exchange. However, major delays caused by the Houthis arguing over the detail of the agreement have prevented major aspects being implemented. Some elements of Saudi Arabia's new plan were already agreed in Stockholm. The plan also stipulates that taxes and fees from Hodeidah port be put into a joint account in Yemen's Central Bank that both the government and the Iranian-backed rebels would be able to access.