A terrible conflict has been raging in Yemen for most of the past five years, with little apparent prospect of an end to the killing, destruction and disease that has often featured on newspaper front pages and in television reports. Inevitably the impact on children and the civilian population has been catastrophic.

But thanks to recent intensive diplomatic initiatives, Yemen and its people can perhaps begin to contemplate the prospect of a more settled future. The agreement signed earlier this week between the internationally recognised Yemeni Government and the separatist Southern Transitional Council has the potential to bring about a lasting peace. It will still nevertheless require further determined, detailed and painstaking negotiation from all sides.

As is often the case in long running conflicts, their origins can be forgotten in the fog of war. When the Yemeni Houthis moved south from their northern homelands, seizing territory and subjecting Yemenis to their brutal rule, it plunged the country into civil war. Al-Qaeda operatives in the Arabian peninsula seized the opportunity to impose their own extremist and violent rule in the east of Yemen.

Stability in the wider Middle East was once again threatened. The formation of a regional coalition backed by the West, prevented instability from spreading beyond the borders of Yemen. Moreover it was the Coalition’s military efforts that eventually brought the combatants to the negotiating table. In particular the successful operation around the port of Hodeida, designed to prevent the illegal smuggling of Iranian weapons to the Houthi rebels, was perhaps the most significant factor leading to the Stockholm negotiations.

That agreement, very slowly being implemented by the Houthis, has seen a significant reduction in the level of violence, which in turn has reduced malnutrition and disease. It has also allowed the flow of aid for reconstruction, primarily from Saudi Arabia and the United Arab Emirates, to reach right across the country.

Similarly a less well reported aspect of the conflict saw Emirati ground forces working with local militias, destroy Al-Qaeda’s control of Eastern Yemen.

The next diplomatic steps will be crucial in ensuring that positive progress leads to permanent peace. The agreement allows for further political negotiations to determine the future constitutional arrangements for Yemen. Rightly, the parties have recognised that this can only be carried through once the fighting has stopped. Saudi Arabia, the UAE, the United States and the U.K. have all given their strong backing to the agreement. Coalition partners and their supporters meeting in London in late April released a joint statement, emphasising their joint “commitment to a comprehensive political solution for the conflict in Yemen”.

The real threat to this regional and international consensus comes inevitably from Iran. It is the Iranian leadership in Tehran that has been a key cause of the conflict continuing. By supplying the Houthi Rebels with a wide variety of weaponry, including advanced missiles and high tech drones, they have encouraged efforts to disrupt Middle East stability by allowing the launch of those weapons against civilian targets in Saudi Arabia.

The way is now open for Iran to finally abandon its military support to the Houthi rebels. It can join in the efforts by its near neighbours in Saudi Arabia and the UAE by deploying its considerable political influence to ensure that the agreement reached at Stockholm in turn leads to a permanent and long lasting peace for Yemen. Iran has an opportunity through these further delicate and difficult negotiations of demonstrating its commitment to regional and international stability. Their outcome could be a test case of Iran’s attitude.

Geoff Hoon was Defence Secretary under Tony Blair.