The breach between the USA and Iran, that had been threatened more or less from the start of Mr. Trump’s presidency, has now finally come to pass. Harsh words and hostile gestures have eventually led to a decisive break, and what was earlier in the realm of angry exchange has taken on a different reality.

Mr. Trump had begun by targeting his predecessor whose policy towards Iran he denounced in extraordinarily tough language, and this was followed by strong action that had earlier seemed on the verge but has now escalated into a confrontational encounter that gives a dangerous complexion to regional events. Iran has once more been drawn into dispute, and is regarded by the USA as a prime source of danger that must be curbed and controlled.

Within this deteriorating scene the greatest risk continues to be associated with nuclear issues, with Iran under continued suspicion of clandestine development of nuclear weapons, though this charge has been firmly denied and lacks concrete evidence.

Dealing with this issue has been a slow and tortuous process, Iran’s tenacious diplomacy being matched by no less resolute efforts from the other side, as they have both striven to reconcile their incompatible demands.

It took numerous rounds of negotiations before the long-standing impasse could be resolved, and then only to a degree, in the waning days of Mr. Obama’s presidency when all sides were eventually able to agree to a process that met their minimum requirements.

The core of this agreement was supervised restraint and inspection of nuclear facilities in Iran, in exchange for which the onerous sanctions on that country were to be lifted, not wholly but in considerable measure.

This outcome was hailed, and legitimately so, as an outstanding achievement that advanced the cause of peace and progress; many regional and global leaders, including several US allies were among the throng of those who supported the agreement.

But within the largely favourable chorus of approval there were discordant notes, especially from the then newly appointed US President, Mr Trump, who felt from the start that the agreement was faulty and needed major restructuring to make it acceptable. He has persisted in this view and has used the great strength of his office to promote these opinions.

This does not appear to have been a collegial decision, and on this issue the USA has been prepared to go it alone, breaking ranks with its friends and allies in pursuit of Mr. Trump’s decision. Important figures from within the US foreign policy establishment may have looked hard at the options before the issue was concluded, though eventually the President’s will prevailed, as was only to be expected.

Now that the matter has been concluded, there is no doubt that Mr Trump’s decision is to be seen as a major development with wide-reaching consequences. For a considerable period of time Iran had been drawn into negotiation on nuclear issues without violating its obligations, which were kept within bounds and did not violate its international commitments on the subject.

There was criticism of some Iranian policies from the start, and some regional actors, especially Israel, did not follow Mr. Obama’s lead on his policy towards Iran. To overcome the criticism was no simple task, and as events have shown negotiating the nuclear deal was the most complicated of tasks, with an important bearing on matters of regional peace that drove the parties to find a way through the nuclear maze.

The strong regret among many members of the international community expressed at this time has much to do with the fear that once again the dangers that have so often afflicted the region, including nuclear uncertainties, have been revived and fresh problems have taken shape. The Middle East has long been regarded as a volatile part of the world and stirring up matters there can only be regarded as undesirable.

Moreover, there are other developments besides the matter of Iran to add to regional problems, such as the US decision to confer recognition on Jerusalem as capital of Israel in place of Tel Aviv: this has been on the anvil for many years but has been kept in abeyance owing to the inherent sensitivity of the issue.

As may have been anticipated, this decision has received a great welcome in Israel but has created a considerable storm in many parts of the Islamic world, and has added to the turmoil caused by the break between Iran and USA. The sharper edge to US diplomacy of the last few months has stirred up the Middle East and added to the uncertainty in that area.

The reaction to these events as seen in India is more or less as might have been anticipated. India has worked hard over the last few years to develop relations with Israel.

This has been a slow and cautious process, as required by circumstances but there has been steady progress, even while India’s ties with the Arab world have also advanced. India has thus succeeded in maintaining a suitable balance in relations within its region, notwithstanding the complexities of the task, its independent approach to Middle Eastern affairs being the key to its regional policy.

The differences between Iran and the USA represent a particular diplomatic challenge for India. One of India’s successful initiatives of the last few years is the way it has drawn closer to Iran and strengthened its ties with that country.

This has something to do with the availability of oil and Iran’s interest in finding a steady market for its large oil resources, and this was for many years what brought the two countries closer. But recent enlargement of their relations has now added significantly to the exchanges between the two countries.

The Chabahar project that links the Iranian coast to the interior of that country has proved to be a success and has opened the way for Indian trade and traffic to Afghanistan and other parts of Asia. India’s strategic interests will also be provided for through the opening of new routes of access based in Chabahar.

India’s efforts have yielded important results, and Iran plays an important part in future plans for the region. Together, India and Iran have already embarked on important schemes from which they will both profit, notwithstanding the adverse views of third parties like the USA in the matter of their cooperation with Iran.

The writer is India’s former Foreign Secretary