Iran and Saudi relations have been wearying over numerous geopolitical issues, for instance, the ambitions for dominance in the region, policies of oil export, and relations with the Western powers, specifically the United States. The two contenders Iran (with a majority of Shia Muslims) and Saudi Arabia (with a majority of Sunni Muslims) have been indulged in proxy wars for years and have backed opposing sides within Yemen, Iraq, Bahrain, Lebanon and Syria. After years of animosity, the two biggest rivals of the Middle East decided to mend their differences and re-establish diplomatic ties last year. The deal was brokered by China on the 10th of March, between the leading officials of both nations. It will have an enormous impact on the Middle East, leading to major developments in the region. However, it might face some challenges given the presence of non-state actors, religious differences, and Saudi’s solid stance on Iran’s nuclear program. The tensions date back to the 1979 revolution of Ayatollah Ruhollah Khomeini which resulted in the formation of an Islamic Republic. The Saudi monarchy which grounded its validity on Islam, feared the expansionist vision of Khomeini. In the subsequent years, the two neighbouring countries boarded on a petulant rivalry brimmed with moments of crisis and hostility. Estimates show that the Al-Saud family spent around $100 billion on their evangelical cause. On the other hand, Iran established Shia groups, for instance, Hezbollah, the Islamic Front for the Liberation of Bahrain, and the Lebanese Party of God to challenge the regional order. Such tactics revealed that both sides positioned Islam at the heart of political and security designs in the region. Both sides positioned Islam at the heart of political and security designs in the region. After a long-standing rivalry, many efforts were made by Iraq and Oman to host talks between Saudi and Iran, however, the reunion by China is central to the debate, as we observe the power competition between the US and China. Saudi plans are much beyond the effort to get involved in US-China rivalry, for instance, Vision-2030 contains a lot of economic projects which are arduous unilaterally, hence the country requires the support of other regional and global actors – to this end, the peace deal has a lot of importance for Saudi. In addition, it carries much-needed relief to millions of people living in the Middle East who were distressed by sectarian violence instigated by Saudi and Iran. Similarly, it would provide an opportunity for economic cooperation on various projects. Given that both countries are resource-rich and have substantial economic potential, the peace deal would allow Saudi and Iran to collaborate in multiple sectors such as energy, communication, climate change, transportation and trade in the region. Besides, the deal may open a door for security dialogues among other regional actors, in particular, Iran and Iraq which have a long history of conflicts and proxy wars. The Saudi-Iran rapprochement possibly reduces the security concerns of the Middle East; however, it seems to be a temporary agreement which might break at any point. First, Saudi Arabia has a solid stance on Iran’s nuclear program. Last year, Crown Prince Muhammad Bin Salman stated in an interview with US Television that Saudi will also go for a nuclear weapon if Iran acquires one. Though Iran may not intend to deter Saudi Arabia with nuclear weapons, both states have a huge adversarial past – a little escalation in crisis will bring the two sides to the brink of war. Secondly, the peace deal might be compromised due to the menace of religious divergence. The differences of opinion might serve as the cause of rivalry in the future, given that both Shiites and Sunnis possess diverse views on Islam. It is a well-known fact that the expansionist policies of Khomeini threatened the Saudi leadership which led to high-level tensions between the two parties. Therefore, as long as religion remains in the political fabric of these two states, the peace deal may not help in achieving a long-lasting peace Moreover, the period after the Arab Spring in 2011 witnessed an astonishing proliferation of non-state actors in the Middle East due to their increased significance in the region. These organizations have undoubtedly performed an important role in campaigns that led to the demise of autocratic regimes in Libya, Yemen, Egypt, and Tunisia. Above all, these groups were supported militarily by Saudi and Iran to pursue their interests in the region. As a consequence, the presence of these non-state actors may compromise the relations of Saudi and Iran in the future. In conclusion, the Saudi-Iran rapprochement plays an important role in shaping the future of the Middle East. It may lead to further agreements and negotiations over security issues between the regional actors. Ranging from technological and economic aspects to climate change initiatives, Saudi and Iran may use the deal as an opportunity to enhance cooperation in these crucial sectors by mutual efforts. Nevertheless, due to the threat of crisis escalation, the deal may not continue for long. The struggle for dominance between Riyadh and Tehran is not a hidden fact anymore. Despite the cultural, religious and ideological differences, both Saudi and Iran had long friendly relations before 1979, which shows that through peace and cooperation, the two neighbours can become a source of regional stability and development. Both sides should engage in peaceful ways to achieve their objectives – the door of diplomacy is always open. The writer is a freelance columnist.