Mojtaba Khamenei says Tehran will eliminate ‘enemy’s abuses of the waterway’ and guard its nuclear and missile programmes

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Iran’s supreme leader has broken his recent silence with a defiant statement hailing Iran’s control over shipping in the strait of Hormuz and vowing to guard the country’s nuclear and missile programmes.

“Today, two months after the largest military deployment and aggression by the world’s bullies in the region, and the United States’ disgraceful defeat in its plans, a new chapter is unfolding for the Persian Gulf and the strait of Hormuz,” Mojtaba Khamenei said in a statement read by a state television anchor.

Defection is damaging to Saudi Arabia’s prestige – and could strengthen the US hand in the region

The United Arab Emirates’ decision to walk out of Opec is a political as much as business decision, and will reignite the simmering rows between the UAE and Saudi Arabia – which had been covered up by their shared anger with Iran over its attacks on the Gulf states since the start of the US-Israel war on Tehran.

In the short term, leaving the oil producing cartel it joined in 1967 gives the UAE the freedom to respond quickly to a long-term prospect of constrained supplies, and to maximise profit. But it is a decision the UAE has considered before, as UAE and Saudi tensions over production quotas have been longstanding.

Exclusive: Officials warn department will also lose access to database of 26,000 verified incidents due to cuts

The Foreign Office unit tracking potential breaches of international law by Israel in Gaza and more recently Lebanon has been closed because of cuts within the department, the Guardian can reveal.

The decision to shut the international humanitarian law cell follows a review by Olly Robbins, the permanent secretary at the Foreign Office dismissed last week by the prime minister over the Peter Mandelson scandal.

Iran’s goal is to maintain chokehold on the global economy, even as some say it could run out of oil storage by Sunday

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Donald Trump’s indefinite shelving of the plan to bomb Iran’s bridges and power stations on Tuesday night is being widely described as leaving the conflict in limbo, but that is anything but the truth.

Pakistan insists the prospect of talks in Islamabad has not evaporated, and positive messages are still being exchanged, but in the meantime the site of kinetic activity has switched from land to sea.

US president’s contradictory statements only make Tehran more wary of anything but the most watertight deal

Donald Trump’s blend of threats and hubristic commentary, often casually dismissive of Iran, has, as much as the continuation of the US naval blockade of Iranian ports, been a key stumbling block to restarting peace talks between the two countries under Pakistan’s mediation in Islamabad.

However much the Iranian foreign ministry insists it will not respond to every social media utterance issued by the US president on Iran, and sometimes there are as many as seven a day, Tehran cannot ignore them all, even if they contradict what the Iranians are being told in private about Trump’s true intentions.

US president’s unreliable style sows diplomatic confusion but leaves Tehran clear on strategic value of strait of Hormuz

Donald Trump’s decision to send US officials to Islamabad for further talks on Monday with Iran just 24 hours after Iran once again closed the strait of Hormuz will signal to Tehran that the strategic waterway remains a bargaining asset beyond parallel.

It will also confirm in Iran’s eyes that the US president’s chaotic approach to diplomacy doubles the need for Tehran to act calmly and strategically – two competencies it believes he totally lacks.

US president’s desperation for war to end has seen him trying to speed through a process he does not fully control

A set of mismanaged and premature media announcements by Donald Trump and Tehran has led to the collapse of progress towards a peace settlement between Iran and the US.

The recent missteps ended with Iran saying it would reinstate a complete block on the movement of commercial shipping through the strait of Hormuz and that it would not allow any of its stockpile of highly enriched uranium to be exported out of the country.

US president will need to show heavy costs of war were worthwhile while Iran must choose between instant and delayed gratification

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If talks between Iran and the US reconvene within the next few days in Islamabad, Donald Trump will have two major political hurdles to overcome – first showing that any deal he secures is better than the one signed by Barack Obama in 2015 and from which he withdraw in 2018, and secondly proving the deal is more favourable than the one on offer in Geneva in February before he launched his war.

Otherwise he will have inflicted massive damage on the world economy when alternatives were available that were less costly in blood and treasure. He will also have to show that Iran has made no permanent gain by taking control of shipping passing through the strait of Hormuz. These are the yardsticks, or tests, around which his negotiating team will be keeping an anxious eye.