Cameron calls Rouhani, discusses Iran's nuclear programme

Becomes the first British premier to call an Iranian leader in over a decade

Prime Minister David Cameron telephoned President Hassan Rouhani today, becoming the first British premier to call an Iranian leader in over a decade, Downing Street said.

Cameron and Rouhani discussed the upcoming negotiations over Iran's nuclear programme, the conflict in Syria and the recent improvements in bilateral ties between London and Tehran, it said in a statement.

"The prime minister became the first British prime minister to call the Iranian president in more than a decade today when he spoke to President Rouhani this afternoon, ahead of this week's nuclear negotiations in Geneva," a Downing Street spokesman said.

They "agreed to continue efforts to improve the relationship on a step by step and reciprocal basis" following the appointment of non-resident charge d'affaires to each others countries last week, the statement said.

The appointment of the envoys was a key step towards improving ties severed after Iranian protesters ransacked the British embassy in 2011.

"On Iran's nuclear programme, both leaders agreed that significant progress had been made in the recent Geneva negotiations and that it was important to seize the opportunity presented by the further round of talks which get underway tomorrow," the statement said.

Cameron "underlined the necessity of Iran comprehensively addressing the concerns of the international community about their nuclear programme, including the need for greater transparency", it said.

"On Syria, there was agreement on the need for a political solution to end the bloodshed," the Downing Street statement said.