Britain's Foreign Secretary Philip Hammond has reopened the British embassy in Tehran, four years after Iranian protesters stormed the building and forced its closure.
In a historic step in the thawing of relations between Tehran and Western powers, Hammond on August 23 declared the British Embassy open and raised the Union Jack flag within the garden of the 19th century residence in the heart of Tehran.
"Today's ceremony marks the end of one phase in the relationship between our two countries and the start of a new one -- one that I believe offers the promise of better," he said.
He added: "Iran is, and will remain, an important country in a strategically important but volatile region. Maintaining dialogue around the world, even under difficult conditions, is critical."
On Twitter.Hammond described the reopening of the British Embassy in Tehran as an "important milestone in improved relations."
Meanwhile, Iran's state-controlled ISNA news agency said on August 23 that the Iranian Embassy in London was simultaneously reopened in London.
Hammond said the embassies initially would function at the charge d’affaires level, but ambassadors should be agreed within months.
The United Kingdom expelled Iranian diplomats from London after a mob in 2011 broke into the British Embassy in Tehran and ransacked the premises.
Inside the embassy, graffiti left by radicals is still visible on doors and walls as a reminder. "Death to England" reads one piece of graffiti above a portrait of Queen Elizabeth.
Outside the embassy, a small group of hard-liners protested the reopening and chanted slogans against Britain. About ten of them were arrested by the police for disrupting "law and order," the official government news agency IRNA reported.
The reopening of the two countries' embassies comes after Iran and six major world powers reached an agreement on Tehran's nuclear development program in July that allows the gradual lifting of international sanctions on Iran.
While in Tehran, Hammond also met with Valiollah Seif, the governor of the Central Bank of Iran. With the recent thaw in diplomatic relations, the foreign minister said Britain wants to work with Iran's central bank to make it easier for banks in the United Kingdom to finance trade and investment in the Persian Gulf country.
He said there is a “huge appetite” on the part of British commercial and industrial businesses to engage in Iran if sanctions are lifted under the nuclear deal agreed last month.
Hammond said Britain’s financial institutions want to support that activity “but it must be done in the proper way.”
Seif said Iran and Britain had a positive relationship in the past and could build on those experiences.
At a joint press conference with Iran’s Foreign Minister Mohammad Javad Zarif held later on August 23, Hammond said "Iran is and will remain a very important country in a strategically important but volatile region."
Hammond said that "our embassies play an important role in maintaining" dialogue between Tehran and London.
Zarif said Tehran and London could resolve "differences through interaction and reaching a mutual understanding."
The British politician is also due to meet with Iranian President Hassan Rohani on August 24 to discuss “issues of mutual interest”, Iran’s official news agency IRNA reported.
Hammond is only the second British foreign minister to visit Iran since the 1979 revolution that toppled the U.S.-backed shah. The last visit was by Jack Straw in 2003.