United Nations: UN chief Ban Ki-moon has welcomed the transition of power in Yemen, saying all sides should now honour their commitments to immediately bring to an end all violence and refrain from further provocations.

The political settlement agreement, signed by President Ali Abdullah Saleh, was an "important step for the people of Yemen in moving their country forward towards a better future," Ban's spokesperson said in a statement.

In the deal brokered by the Gulf Cooperation Council, Saleh handed over power to his vice-president Abdrabuh Mansur Hadi, bringing to an end his 33-year-old rule in Yemen.

Ban said the people of Yemen have endured "great suffering and hardships" and called on all sides to "honour their commitments made in the agreement in good faith".

He said the agreement's success depended on its full implementation.

The UN Secretary General said Yemeni authorities should ensure all violence in the country is brought to an immediate end and they should refrain from any further provocations, working towards a fully inclusive transition process that meets the legitimate demands of the Yemeni people.

Under the agreement, presidential elections will be staged within 90 days.

Ban acknowledged Saleh's commitment to enable the transition process to begin and noted the constructive roles played by Hadi, the GCC, members of the Security Council and the European Union in promoting a peaceful transition.

He said the UN is "fully committed" to assisting the people of Yemen in bringing the transition process to a successful conclusion.

UN Special Adviser on Yemen, Jamal Benomar called the transition of power "an important milestone towards restoring peace and stability, maintaining national unity and territorial integrity, and laying the foundation for economic recovery".

 Over the next two years, a government of national unity will establish a national dialogue to ensure that a broad section of society takes part in determining Yemen's future, with a constitutional review to follow.

 "These steps will create a strong basis for a fully inclusive and participatory transition process, giving civilsociety, including the youth and women, a true stake in Yemen's future," he said.

 "Towards this end, the parties have agreed to engage immediately with the youth movements in the squares to seek their support for and active participation in the transition process".

 The agreement follows months of deadly clashes between supporters and opponents of Saleh and his regime, part of the Arab Spring movement that has swept the Middle East and North Africa this year.