Britain, in a move to revive its diplomatic relations with Iran, appointed its non-resident charge d'affaires to Tehran.
The announcements reflect a thaw in relations with the West and comes after Iran and six world powers, including Britain, came close to a preliminary agreement about Tehran's nuclear program at the weekend.
Britain's Foreign Office said Ajay Sharma, currently the head of the ministry's Iran department, will take up the post immediately.
Iran's foreign ministry spokeswoman Marzieh Afkham also said on Monday Islamic Republic had assigned Mohammad-Hassan Habibollahzadeh as its non-resident charge d'affaires and introduced him to the British government.
Afkham added that Habibollahzadeh is to leave Tehran for London soon to make assessments about Iranian assets and buildings in the UK and make preparations for resumption of activities of the consular section of Iran Embassy in London.