DUBAI (Reuters) - A senior British official and nuclear negotiator visited Iran on Monday to discuss upgrading relations severely damaged over an Islamist mob raid on the British embassy in Tehran in 2011.
Simon Gass, a former ambassador in Tehran and now London's point man in six-power nuclear talks with Iran, was expected to address "bilateral and international issues" during his one-day visit, the official Iranian news agency IRNA said, quoting foreign ministry official Majid Takht-Ravanchi.
"There is the likelihood of a rise in the level of diplomatic ties between Tehran and London," said Takht-Ravanchi, who is among Tehran's negotiators in the nuclear talks with the United States, Russia, China, Britain, France and Germany.
Gass is the most senior British diplomats to visit since Britain broke ties over the attack by Islamic hardliners on its embassy. It was triggered by allegations that London was behind mass protests that followed the disputed 2009 re-election of then-President Mahmoud Ahmadinejad. Britain denied this.
Iranian-British relations have thawed somewhat since the election last June of moderate Hassan Rouhani as president. Britain appointed a non-resident charge d'affaires to Iran in November, reviving direct ties, a step reciprocated by Tehran.
A British parliamentary delegation led by former foreign secretary Jack Straw visited Tehran in January.
In a statement issued in London on Monday, the Foreign Office described Gass's visit as "the next stage in the step-by-step approach to improving relations" with Tehran, following a series of trips by Charge d'Affaires Ajay Sharma.
Iran and Britain had normalized relations in 1999, a decade after revolutionary leader Ayatollah Ruhollah Khomeini's fatwa that proclaimed British author Salman Rushdie should be killed for writing his novel "The Satanic Verses".
Iran and Britain have had a troubled history dating back to British oil interests in Iran and the U.S.-British role in the 1953 overthrow of democratically elected nationalist Prime Minister Mohammad Mossadegh that re-established the autocratic rule of pro-Western Shah Mohammed Reza Pahlavi.
The shah was toppled by the 1979 Islamic Revolution.
(Reporting by Mehrdad Balali; Editing by Yara Bayoumy and Mark Heinrich)