Iran's former nuclear negotiator Hassan Rowhani has entered the race to succeed President Mahmoud Ahmadinejad, accusing the incumbent of needlessly incurring crippling economic sanctions.

"I have come forward to save Iran's economy and forge a constructive interaction with the world through a government of wisdom and hope," Iranian media quoted Rowhani as saying in a speech to supporters on Thursday.

Rowhani, 64, headed the nuclear negotiating team that served under reformist president Mohammad Khatami before Ahmadinejad took power in 2005. He joins a field of more than a dozen hopefuls for the June election.

Ahmadinejad is barred by the constitution from standing for a third consecutive four-year term.

In 2003, Rowhani led the talks with the West at which Tehran agreed on a moratorium on its nuclear drive. The suspension lasted for around two years.

Rowhani, who resigned in 2005, pledged that if elected he would rescue the sharply deteriorating economy by mending relations with the international community.

"This administration made fun of sanctions, deriding them as scrap paper, while we could have avoided them or to some extent reduced" their effect," he said.

Rowhani was referring to a speech by Ahmadinejad in which he famously dismissed the six separate resolutions adopted by the UN Security Council over Iran's nuclear programme as "scrap paper".

Source: Agencies