Twenty-one years ago, on my recommendation, the UN general assembly named 2001 the year of “dialogue among civilisations”, and signalled its commitment to peace and its rejection of war and violence. The Iranian people, despite their own historic grievances and troubled history, opened a hopeful new chapter of engagement and dialogue with the Great Powers (US, UK and Russia). These hopes, however, were dashed by the terrorist atrocities of 11 September, 2001 and their tragic aftermath in devastating wars in west Asia. The catastrophic wars of Iraq and Afghanistan and other interventions in the region exacerbated already extant problems, and paved the way for the growth of international terrorism, civil wars in Syria and Iraq, and the depredations and war crimes still unfolding in Yemen. These conflicts have made the region unsafe and have impinged on security around the world.

In the same period, the development of Iran’s peaceful nuclear programme became a test of the dialogue on peace. In order to build trust with the international community my administration sought dialogue, and after years of difficult and tumultuous negotiations, President Rouhani’s government succeeded in concluding the Joint Comprehensive Plan of Action (JCPOA) – known as the Iran nuclear deal – with six other world powers.

Iran has repeatedly declared that it is not seeking to build a nuclear weapon. In addition to observing its obligations under the non-proliferation treaty (NPT), as a gesture of goodwill Iran accepted the JCPOA’s measures to ensure transparent verifiability of the peaceful nature of its civilian nuclear programme. The successful conclusion of the JCPOA was a major achievement which showed that reciprocity and mutual trust between Iran and the E3+3 were not only possible, but desirable. Furthermore, it acted as an important basis on which to build, containing within it the prospect of more fruitful and positive relations between our respective nations in the future. Sadly, Iran was the only country to abide by all the provisions of the JCPOA, while the other signatories have either breached or shirked their responsibilities under its terms.

While Iran was playing a decisive role in defeating the Islamic State’s reign of terror, the Trump administration decided to initiate a new round of hostilities against my country by illegally withdrawing from the Iran nuclear deal, violating UN security council resolution 2231 that the US had itself jointly sponsored, and waging a campaign of economic sanctions against the Iranian people. President Trump is thus punishing Iran and indeed the world community not for violating the JCPOA, but for complying with this UN-sanctioned international legal agreement. By exiting the JCPOA, the Trump administration has moved against the very principles of dialogue, engagement and coalition-building. It has spurned the cause of peace. Unrelenting sanctions and what is effectively a blockade on Iran impose collective punishment on a nation that has done absolutely nothing wrong. The present US administration is ratcheting up tensions in the Persian Gulf, making a conflagration or even a full-scale war between our two countries increasingly likely.

But the reimposition of brutal sanctions and renewed military threats will not force the Iranian government or my people into submission. Sanctions, like terrorism, are indiscriminate in their targets and ruinous in their consequences.

Today, the Middle East once again faces a crisis not of its own making; a crisis which was both unnecessary and avoidable. It doesn’t have to be this way, and escalating tensions can still be defused. Cool heads must prevail if the region is not going to find itself dragged into yet another violent maelstrom. This cycle of imperious unilateralism and the substitution of military solutions for political ones must stop, and the US administration must respect its international obligations by choosing dialogue over coercive diplomacy and threats of war.

As someone who has made it his life’s mission to defend the dialogue of cultures and civilisations, world peace, democracy, tolerance and human rights, I express my deep concern for the future of the Iranian nation and other nations of our region. It is in this spirit that I call on people of conscience in the US and across the world to promote peace and “dialogue among civilisations” instead of promoting the idea of a “clash of civilisations”. We must form a #CoalitionForPeace that says #NoWarWithIran to prevent disaster. With a view to the acute level of tensions in the Persian Gulf region, the situation is both fragile and explosive.

Despite the pressure coming from some of his advisers, President Trump still has the choice to reverse his administration’s unnecessary escalation. He should be aware that Iranians are steadfast. For well over a century since our 1905 constitutional revolution, Iranians have fought to preserve our dignity and independence. The JCPOA negotiating process was proof of Iran’s good faith and commitment to a respectful international peace. The question is whether the current US administration is willing to respond in kind, instead of continuing to issue insults and threats and using the kind of colonial language more befitting of 19th-century imperial administrators than a 21st-century world power.

It is easy to destroy, but far harder to build. Obstacles to a lasting peace are real. But they are not insurmountable. We must be proactive in our advocacy for peace and dialogue for our own sake and that of future generations. Dialogue, empathy and a willingness to listen to one another is the only way towards hopeful horizons of a bright future.

• Mohammad Khatami was president of the Islamic Republic of Iran from 1997 to 2005