[2] UK seeds a number of proximity conflicts between Iran and its neighbouring states like Azerbaijan[3] on the countries' borders, Afghanistan[4] on the Hirmand river and United Arab Emirates[5] on possession of three disputed islands.

Anglo-Persian relations picked up momentum as a weakened Safavid empire, after the short-lived revival by the military genius Nader Shah (r. 1736-1747), eventually gave way to the Qajarid dynasty, which was quickly absorbed into domestic turmoil and rivalry, while competing colonial powers rapidly sought a stable foothold in the region.

After repelling Nasereddin Shah's attack in Herat in 1857, the British government assigned Frederic John Goldsmid of the Indo-European Telegraph Department to determine the borders between Persia and India during the 1860s.

[8] In 1872, the Shah signed an agreement with Baron Julius de Reuter, which George Nathaniel Curzon called "The most complete and extraordinary surrender of the entire industrial resources of a kingdom into foreign hands that has ever been dreamed of".

[10] Similarly, the "Tobacco fatwa", decreed by Grand Ayatollah Mirza Hassan Shirazi was an incident which raised popular resentment against the British presence in Persia in lieu of a diplomatically decapitated and apathetic Qajar throne.

[citation needed] The great tremor of the Persian political landscape occurred when the involvement of General Edmund Ironside eventually led to the rise of Reza Shah Pahlavi in the 1920s.

By the 1920s APOC's extensive installations and pipelines in Khuzestan and its refinery in Abadan meant that the company's operations in Iran had led to the creation of the greatest industrial complex in the Middle East.

The attempt to revise the terms of the oil concession on a more favorable basis for Iran led to protracted negotiations that took place in Tehran, Lausanne, London and Paris between Teymourtash and the Chairman of APOC, Sir John Cadman, spanning the years from 1928 to 1932.

Rejecting the cancellation, the British government espoused the claim on behalf of APOC and brought the dispute before the Permanent Court of International Justice at The Hague, asserting that it regarded itself "as entitled to take all such measures as the situation may demand for the Company's protection."

The new Shah, Crown Prince Mohammad Reza Pahlavi, signed a Tripartite Treaty Alliance with Britain and the Soviet Union in January 1942, to aid in the allied war effort in a non-military way.

Relations suffered a setback in 2002 when David Reddaway was rejected by Tehran as London's ambassador, on charges of being a spy, and further deteriorated two years later when Iran seized eight British sailors in Arvand River near the border with Iraq.

[citation needed] In November 2011, Britain severed all ties with Iranian banks as part of a package of sanctions from the US, UK and Canada aimed at confronting Tehran’s nuclear programme.

[35] On 21 June 2004, eight sailors and Royal Marines were seized by forces of the Revolutionary Guards' Navy while training Iraqi river patrol personnel in the Persian Gulf.

Despite the political pressure and sanctions, a probe by customs officers suggests that at least seven British arms dealers have been supplying the Iranian air force, its elite Revolutionary Guard Corps, and the country's controversial nuclear ambitions.

Other examples involve a British millionaire arms dealer caught trading machine-guns used by the SAS and capable of firing 800 rounds a minute with a Tehran-based weapons supplier.

"In the worst-case scenario, George Bush may perhaps persuade the president-elect to carry out an ill-conceived operation against Iran, prior to January 20, 2009—that is, before the regime is handed over and he ends his presence in the White House.

[47] After this event, the UK Government responded strongly demanding that the Iranian authorities release the British staff immediately as it stated that Iran's accusations are baseless without evidence.

[50] Eslamain wrote, "It seems that the University of Oxford has stepped up involvement in a politically motivated campaign which is not only in sharp contract with its academic objectives, but also is linked with a chain of events in post-Iranian presidential elections blamed for British interference both at home and abroad".

"[51] Eslamain asked for the university's governing board to be informed of "the Iranian views", and finished by saying, "Surely, your steps to achieve your attractions through non-politically supported programs can better heal the wounds of her family and her nation.

"[51] Following publication of the Iranian letter, The Times was told by UK diplomatic sources, speaking anonymously, that the scholarship had put "another nail into the coffin" of relations between Britain and Iran.

[52] If the government had been asked, the sources were reported as saying, it would have advised against the move, because it was felt that Iran would see it as an act of provocation, and because it would interfere with efforts to free Iranians working for the British Embassy in Tehran who had been detained for alleging participating in the post-election protests.

He said any attempt by Iran to block the strategically important waterway in retaliation for sanctions against its oil exports would be “illegal and unsuccessful” and the Royal Navy would join any action to keep it open.

British defence officials met US Secretary of Defense Leon Panetta on 6 January to criticize other members of the NATO for not being willing to commit resources to joint operations, including in Libya and Afghanistan.

[61][62] The following day, UK officials reported its intention to send its most powerful naval forces to the Persian Gulf to counter any Iranian attempt to close the Strait of Hormuz.

[66] British prime minister David Cameron and Iranian President Hassan Rouhani met on the sidelines of a United Nations in September 2014, marking the highest-level direct contact between the two countries since the 1979 Islamic revolution.

[84] On 14 July 2019, British Foreign Secretary Jeremy Hunt said Grace 1 could be released if the UK received guarantees the oil — 2.1 million barrels worth[85] — would not go to Syria.

[86] On 19 July 2019, Iran media reported that the Swedish owned but British-flagged oil tanker Stena Impero had been seized by the Iranian Revolutionary Guard in the Strait of Hormuz.

[94][95][96][97] On 26 August, Iranian government spokesman Ali Rabiei announced that the 2.1 million barrels of crude had been sold to an unnamed buyer, in either Kalamata, Greece or Mersin, Turkey.

[98] On 15 August 2019 the UK's new Boris Johnson-led government agreed to join the U.S. in its Persian Gulf maritime security Operation Sentinel, abandoning the idea of a European-led naval protection force.

"[111] In April 2023, the European Union, along with Britain, imposed sanctions on over 30 Iranian officials and organizations, including units of the revolutionary guards, due to their alleged involvement in human rights abuses during a crackdown on civil unrest.