
The Pentagon has released new color pictures which it says are proof of Iran's involvement in last week's tanker blasts - as America deploys 1,000 more troops to shore up its defenses in the tense Middle East.

Taken from a Navy helicopter, the pictures purport to show Iranian Revolutionary Guard members in an armed patrol boat removing an unexploded limpet mine from the Kokuka Courageous, one of the tankers hit by an explosion in the Gulf of Oman.

The Iranians left behind a handprint and fragments of the mine, Washington says, releasing the images which also appear to show a hole in the side of the ship.

The images, which are much clearer than the grainy black-and-white footage which the Pentagon released last week, were published last night to bolster America's claim that Iran was behind the explosions.

Secretary of State Mike Pompeo has reached out to European and Asian leaders to convince them, after Germany cast doubt on the U.S. claims.

'Iran is responsible for the attack based on video evidence and the resources and proficiency needed to quickly remove the unexploded limpet mine,' Central Command said in a statement accompanying the new pictures.

Tehran has denied involvement but the explosions have prompted another exchange of angry rhetoric, at a tense moment in Middle East politics as Iran is set to breach its nuclear commitments.

The Pentagon is sending another 1,000 troops for 'defensive purposes to address air, naval and ground-based threats in the Middle East', acting defense secretary Patrick Shanahan said.

Shanahan insisted that 'the United States does not seek conflict with Iran', but said the deployment was 'to protect our national interests'.

Patrol boat: The U.S. military says this armed patrol boat is a Revolutionary Guards vessel which has just removed a limpet mine from the side of the Kokuka Courageous. The pictures were taken from an MH-60R helicopter, which can get closer than a drone or a P-8 Poseidon airplane

Removal: The Pentagon says this is members of the Revolutionary Guard's patrol boat's crew removing an unexploded limpet mine from the side of the tanker

Alongside: One image shows the patrol boat on the port side of the Japanese-owned tanker after another mine exploded on the other side of the vessel

Key to the claim: The crosshairs in this image are over the spot on the hull of the Courageous which was left marked by the removal of the magnetic limpet mine, according to the Pentagon

Where the 'mine' was: This is the part of the hull of the Courageous where the Pentagon says Revolutionary Guards placed a limpet mine then removed it when it failed to explode

Part of device: The Pentagon released this image of what it says is aluminum and green composite left attached to the Courageous when the limpet mine was removed

Red handed? The Pentagon says this is a handprint from an individual who removed an unexploded limpet mine from the side of the Kokuka Courageous

Timeline: Escalating Middle East tensions May 5: The White House announces the deployment of the USS Abraham Lincoln carrier strike group to the Middle East over unspecified threats from Iran. May 8: Iran threatens to breach its nuclear commitments if world powers do not improve the terms of their deal. Washington hits back with sanctions. May 12: Four tankers, two of them Saudi ships, are subject to mysterious 'sabotage' attacks off the UAE coast. Washington and Saudi Arabia blame Iran, which denies involvement. May 14: Yemen's Houthi rebels, which are backed by Iran, strike a major east-west oil pipeline in Saudi Arabia, knocking it out of service. May 19: President Trump issues a stark warning to Tehran, saying: 'If Iran wants to fight, that will be the official end of Iran. Never threaten the United States again!' June 6: A UAE investigation finds that divers targeted the four ships in May using limpet mines, carrying out an attack with a 'high degree of sophistication'. It does not name Iran. June 12: The Houthi rebels attack a regional airport in Saudi Arabia, injuring 26. A Saudi-led coalition in Yemen accuses Iran of equipping them with a missile. June 13: Two more tankers, the MT Front Altair and Kokuka Courageous, are hit by explosions in the Gulf of Oman. Forty-four sailors are forced to abandon their ships amid a huge fireball on the Altair. It comes as Iran is holding high-stakes talks with Japan's PM Shinzo Abe in a bid to defuse the crisis. Later that day U.S. Secretary of State Mike Pompeo says Iran was behind the explosions. Tehran denies what it calls a 'baseless' claim, accusing the U.S. of 'Iranophobia', and says it is 'suspicious' about the timing during Mr Abe's visit. June 14: Iranian president Hassan Rouhani calls America a 'threat to global stability' as tensions rise. President Trump says the apparent attack has 'Iran written all over it'. June 17: Iran says it will surpass the uranium stockpile limit under the 2015 deal. The U.S. calls it 'nuclear extortion' and releases new pictures which it says are proof of Iran's involvement in attacking the two ships on June 13. They are said to show Iran's Revolutionary Guard removing an unexploded limpet mine from the Kokuka, allegedly leaving a mark and handprint. Advertisement

Shanahan stepped up the rhetoric on the alleged Iranian role in the tanker attacks, saying that they 'validate the reliable, credible intelligence we have received on hostile behavior by Iranian forces and their proxy groups that threaten United States personnel and interests across the region.'

'The action today is being taken to ensure the safety and welfare of our military personnel working throughout the region and to protect our national interests,' he said.

It came after a day which saw Iran announce it was close to breaking limits on uranium enrichment which it had accepted under the nuclear deal which Trump quit last year.

That prompted the White House National Security Council to say in a statement: 'President Trump has made it clear he will never allow Iran to develop nuclear weapons.'

Today Tehran insisted it was not seeking a conflict. 'Iran will not wage war against any nation,' president Hassan Rouhani said in a speech broadcast live on state TV. 'Those facing us are a group of politicians with little experience.'

He added, 'Despite all of the Americans' efforts in the region and their desire to cut off our ties with all of the world and their desire to keep Iran secluded, they have been unsuccessful.'

Shanahan's department also released the new pictures, one of which showed a large hole on the side of the Courageous, above the water line, that officials say appears to have been caused by another mine, on the other side of the tanker.

Britain has backed the American claim, saying it was 'almost certain' that Iran was behind the attacks on the Kokuka and the MT Front Altair.

But Germany had voiced caution about the claims, saying that 'we'll take our time' and adding that the evidence so far had only come from one side.

Donald Trump had suggested the original images were taken on night vision cameras, but the new pictures make clear that they were taken by daylight.

The military say that the new images it unveiled show the Iranians put limpet sides above the water line on each side of the vessel and returned to remove the unexploded device when it failed to go off.

They left behind parts of the device and a handprint, Central Command claims.

Blast: The military released new images of what it says is hull penetration and blast damage on the starboard side of the Japanese owned tanker Kokuka Courageous, which was sustained on June 13 and photographed by the U.S. the next day

View from the inside: This is what the U.S. military says is the damage to the Kokuka Courageous caused by a limpet mine allegedly planted by Iranian Revolutionary Guards

Port side damage: This is one of the new images of the impact on the Courageous. 'Iran is responsible for the attack based on video evidence and the resources and proficiency needed to quickly remove the unexploded limpet mine,' Central Command said in a statement

Seen from space: This is the Kokuka Courageous anchored on Monday offshore at the port of Fujairah in the United Arab Emirates

What the military says happened: How the Pentagon describes events last Thursday. the times are in Zulu time - standardized military time. Local time is four hours ahead

Bloomberg News reported that the Pentagon also revealed what it says is a new timeline of the attacks, saying that U.S. forces were first alerted to the attacks by the Front Altair tanker at 7.12 a.m. local time (4.12 a.m. British summer time, and 11.12 p.m. Wednesday EST).

That was followed by an explosion reported at 8 a.m. on the Courageous - although its crew said that there was an external projectile, not a mine.

And four hours afterwards, the military says that an Iranian fast patrol boat of the Gashti class was seen alongside the Courageous removing what it says is a limpet mine from the vessel.

The move came after the White House accused Iran of 'blackmail' after Tehran warned it would break uranium stockpile limits in retaliation for the oil tanker accusations.

A US National Security Council spokesman said today: 'President Trump has made it clear that he will never allow Iran to develop nuclear weapons. The regime's nuclear blackmail must be met with increased international pressure.'

The American response comes after Iran's atomic energy agency said they would ramp up their output to near weapons-grade levels within ten days.

Behrouz Kamalvandi, of the atomic energy agency, said uranium enrichment levels would soar to 20 per cent from the current 3.67 per cent and would only be reversed if other parties in the Iran Deal 'lived up to their commitments.'

It comes after Washington blamed Iran for attacks on two oil tankers in the Gulf of Oman last week, almost exactly a month after similar attacks which were also blamed on the country.

French president Emmanuel Macron urged Iran to be 'patient and responsible' with the Obama-era pact as EU foreign ministers look to salvage the crumbling agreement.

Israeli Prime Minister Benjamin Netanyahu said it was vital that 'snapback sanctions' were imposed should Iran plough ahead with uranium enrichment.

Behrouz Kamalvandi (left), Iran's spokesman for its nuclear energy agency, said that Iran will breach the nuclear pact signed with the Obama White House by June 27

It comes after fresh attacks against two oil tankers in the Gulf of Oman last week which Washington has blamed on Tehran

British Foreign Secretary Jeremy Hunt has backed the Americans in saying Tehran was 'almost certainly' behind the attacks.

'Today the countdown to pass the 300 kilogrammes reserve of enriched uranium has started and in 10 days time... we will pass this limit,' Kamalvandi said.

The move 'will be reversed once other parties live up to their commitments,' he added, in an apparent reference to the nuclear treaty.

How is uranium enriched to weapons-grade levels? Enriching uranium means boosting its concentration of an isotope called U-235, which powers nuclear reactions, and stripping out another unwanted isotope called U-238. When uranium is mined, it typically has about 140 atoms of the unwanted isotope U-238 for every atom of U-235. Refining it to a purity of 3.67 per cent, the level now allowed by the nuclear deal, means removing 114 atoms of U-238 for every atom of U-235. Boosting its purity to 20 per cent means removing 22 more unwanted isotopes per atom of U-235, while going from there to 90 per cent purity means removing just four more per atom of U-235, he noted. Ninety percent is considered weapons-grade material. That means going from 20 per cent to 90 per cent is a relatively quicker process than going from 3.67 per cent to 20 per cent. Advertisement

Monday's announcement brings forward a July 7 deadline that Tehran had set to salvage the nuclear deal after Donald Trump tore up the pact a year ago.

Tehran had asked European signatories - including France , Germany and Britain - to guarantee it the economic benefits it was promised under the deal or it would stop complying.

Diplomats including Germany's foreign minister had travelled to Tehran in hopes of salvaging the deal - but after Washington imposed fresh sanctions on Iran it made those efforts all-but impossible.

Kamalvandi said on Monday that it is not too late for the nuclear deal 'if European countries act', warning that they will not get another chance to do so.

He added that Iran will enrich uranium to 'any level' depending on the country's needs, and that it currently needs uranium enriched to 5 per cent and 20 per cent.

Under the deal, Tehran only enriches uranium to 3.67 per cent, the minimum level needed to fuel a nuclear power station.

Kamalvandi said Monday that the country needs 5 per cent enrichment for its nuclear power plant in southern Iranian port of Bushehr and 20 per cent enrichment for a Tehran research reactor.

Weapons-grade uranium is enriched to 90 per cent, but going from 20 per cent to 90 per cent is a much quicker process than going from 3.67 per cent to 20 per cent.

Enriching to any level above 3.67 per cent would put Iran in breach of the pact forged under the Obama administration.

The US has released video which it claims shows an Iranian boat removing a limpet mine from the side of one of the vessels in an attempt to hide evidence

Iran will breach uranium stockpile limits set in the deal after quadrupling its output and will begin enriching uranium up to 20 per cent, just one step away from weapons-grade level (pictured, Iran's nuclear power plant in Bushehr)

Kamalvandi's comments come in the wake of suspected attacks on oil tankers last week in the region that Washington has blamed on Iran.

In the face of scepticism, US Secretary of State Mike Pompeo said on Sunday that there is no disputing the evidence gathered by American intelligence agencies.

The US has released a video which it claims shows an Iranian boat removing two limpet mines from one of the tankers in an attempt to hide evidence.

'I wouldn't have said it if the intelligence community hadn't become convinced that this was the case,' Pompeo told CBS on Face the Nation Sunday morning.

'I will concede there are countries that just wish this would go away, and they want to act in a way that is counterfactual,' he added.

Germany's foreign minister Heiko Maas said that Germany has still not decided who is to blame for the tanker attack, ahead of a meeting of European foreign ministers

A fireball erupted on the Norwegian-owned MT Front Altair after a suspected torpedo attack caused three explosions, forcing the crew to abandon ship.

Sailors on the Japanese-owned Kokuka Courageous also had to flee after it was hit by another explosion, in a pair of attacks which left the Middle East on high alert.

Tehran has said it is 'suspicious' about the timing of the explosions during a visit by Japan's leader Shinzo Abe, and implied that Washington may have staged the attack to justify increased hostility in the region.

On Monday Heiko Maas, Germany's foreign minister, stressed that his country has not yet made up its mind about who was behind the tanker attacks.

Maas said Germany and others need a clearer picture before wading into a diplomatic conflict which could have serious implications in the Middle East.

He added that U.S. and British intelligence needs to be compared with other information from allies. 'We have to be very careful,' he said.

EU foreign policy chief Federica Mogherini said it was not a time to jump to action without proper information.

'The maximum restraint and wisdom should be applied,' she said ahead of the monthly foreign ministers meeting in Luxembourg.