Threats and warnings between Tehran and western powers spiked on Tuesday amid frustration over the regional military activities of Iran and its partners, as well as Europe’s continued failure to abide by the terms of a 2015 nuclear deal it seeks to uphold.

The UK, Germany and France issued a joint statement late on Monday blaming Iran for the 14 September attack on Saudi oil facilities that briefly took 50 per cent of the kingdom’s petroleum production offline, as Boris Johnson voiced support for Donald Trump’s attempt to forge a “new deal” with Iran.

Prime minister Johnson called for a “Trump deal” to replace the landmark 2015 deal signed under Barack Obama, which took years of diplomacy to forge. Mr Johnson said the US president was the “one guy” who could negotiate a new nuclear pact.

Europeans also called on Iran to accept negotiations that would include regional issues and its missile programme, bringing the countries’ position closer to that of hardliners in the White House.

Iran’s foreign minister Mohammad Javad Zarif responded with fury, accusing Europeans of failing to conduct business with Iran despite the terms of the nuclear deal and writing in a tweet that there would be “no new deal before compliance with the current one”.

Hours later, rockets or mortars landed in Baghdad’s Green Zone, which houses the US and UK embassies and the United Nations mission to the country.

Tensions high as Trump approves new Iran sanctions: In pictures Show all 17 1 /17 Tensions high as Trump approves new Iran sanctions: In pictures Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, their surface-to-air missile is seen as it shoots down a US surveillance drone EPA Tensions high as Trump approves new Iran sanctions: In pictures This photo shows US RQ-4A Global Hawk unmanned surveillance drone. A drone of this model was shot down by Iran on Thursday 21 June AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures An oil tanker is on fire after it was subject to a suspected attacked at the Gulf of Oman on June 13. The US has blamed Iran for the attack Reuters Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, debris from the downed US drone is seen after it was recovered from Iranian waters AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures US President Trump holds up a signed executive order to increase sanctions on Iran on 24 June AP Tensions high as Trump approves new Iran sanctions: In pictures Iranian President Rouhani stated in a televised address that the White House is "afflicted by mental retardation" following the increase in sanctions on 25 June EPA Tensions high as Trump approves new Iran sanctions: In pictures An Iranian navy boat tackles the fire on the Norwegian owned Front Altair oil tanker after it was hit in a suspected attack AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, debris from the downed US drone is seen after it was recovered from Iranian waters AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures A screenshot from a video released by the US Department of Defense that the US claims to show Iranian removing an unexploded limpet mine form the hull of the Japan-owned ship that was attacked in the Gulf of Oman on June 13 Getty Tensions high as Trump approves new Iran sanctions: In pictures An item reportedly found on the Japan-owned oil tanker that was attacked on June 13 in the Gulf of Oman AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures A handout photograph from the US Department of Defense shows a composite material that the US claim was left behind on the hull of the Japan-owned oil tanker following the removal of an unexploded limpet mine Getty Tensions high as Trump approves new Iran sanctions: In pictures A view from the cabin of an Iranian navy boat as it tackles the fire on the Norwegian owned Front Altair oil tanker after it was hit in a suspected attack EPA Tensions high as Trump approves new Iran sanctions: In pictures Release by US government A picture released by U.S. Central Command shows damage to the hull of the oil tanker Kokuka Courageous. The picture suggests that the ship is 'likely' to have been hit by a mine as the US Secretary of State Mike Pompeo moves to blame Iran for the suspected attack Reuters Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures Release by US government A picture released by U.S. Central Command shows damage to the hull of the oil tanker Kokuka Courageous. The pictures suggests that the ship is 'likely' to have been hit by a mine as the US Secretary of State Mike Pompeo moves to blame Iran for the suspected attack EPA

No one was injured. But though there was no claim of responsibility, suspicion for the attack fell on Iranian-allied Shia militias that largely control the southern Baghdad neighbourhood from which the projectiles were fired.

“We have made clear that attacks on Coalition personnel and facilities will not be tolerated and Coalition Forces retain the right to defend ourselves,” said a statement issued by US-led forces combating Isis remnants in Iraq.

In Tehran, the talk is increasingly of a potential armed conflict with the west.

“Today, enemies, who are fearful of a war with Iran, have taken the path of economic terrorism,” Maj Gen Mohammad Baqeri, Iran’s army chief of staff, said in a fiery speech before parliament on Tuesday, according to the Tasnim news agency.

“We have repeatedly warned the enemies that if they invade this country, the result of this invasion will be captivity and defeat.”

The signs of deteriorating relations came during a week of diplomatic intrigue and meetings at the annual United Nations General Assembly in New York that even a few weeks ago many had hoped would herald a potential meeting between Iranian and US officials.

The US arguably sparked the current crisis last year when it unilaterally withdrew from a 2015 nuclear deal that placed limits on Iran’s atomic energy and research programme in exchange for normalised trade ties with the west.

As part of a “maximum pressure” programme designed by ideologically driven Washington hardliners, President Trump reimposed sanctions on Iran and vowed to use American levers of control on the world economy to punish any country or entity that purchased its oil or sold it non-humanitarian goods.

The sanctions have badly damaged Iran’s economy but have failed to rein in its missile programme or its support for armed allies across the Middle East. Still, Brian Hook, the State Department’s Iran envoy, said in a speech on Monday that the US stance was successful because it was “making the regime’s extremist foreign policy and the ideology that drives it more expensive than ever before”.

Though European nations said they opposed Mr Trump’s Iran policy, they have largely submitted to the US restrictions, declining to encourage or allow any trade that would spark the ire of Washington.

For a year, Iran abided by the terms of the nuclear deal, even as Europeans failed to come up with a mechanism that would allow trade.

But since May, Iran and its allies began ratcheting up tensions in the Persian Gulf with the seizures of ships and alleged attacks on vessels, while Tehran slowly lowered its adherence to the nuclear deal by ramping up the enrichment of uranium.

The attack on the Saudi oil facilities in Abqaiq appeared to have spooked Europe, and possibly changed the calculations of leaders in western capitals.

“It is clear to us that Iran bears responsibility for this attack,” said the joint statement by London, Paris and Berlin.

Donald Trump on Iran: 'I don't want a war but US is more prepared than any country'

“There is no other plausible explanation. These attacks may have been against Saudi Arabia but they concern all countries and increase the risk of a major conflict.”

Still both Europe and Iran remained open to talks. Iranian president Hassan Rouhani was scheduled to hold a meeting in New York with Mr Johnson after conferring on Monday with French president Emmanuel Macron.

“We are committed to continuing our diplomatic efforts to create conditions and facilitate dialogue with all relevant partners interested in de-escalation of tensions in the Middle East,” said the joint statement.

The husband of Nazanin Zaghari-Ratcliffe, a dual British-Iranian national detained in Tehran in 2016, urged Mr Johnson to use his scheduled meeting with the Iranian president to call for his wife’s release, and said it was time for the former foreign secretary to make amends.

Richard Ratcliffe said that Mr Johnson “didn’t take any responsibility for his mistakes” as foreign secretary.

Mr Johnson said Ms Zaghari-Ratcliffe was in Iran “teaching people journalism” – despite her family’s insistence she was there to visit relatives.