Speaking to FNA, Najjar described the statement by the Obama administration, which recognized Iran's right to use nuclear energy, as a positive step ahead, if it is for real.
"The opposition of the US administration with this legal and natural right of Iran was the result of the extremist vanity and selfishness of the Bush administration," he added.
He underlined that Iran's principal policy is based on using nuclear energy for peaceful purposes, reminding that Tehran has always laid emphasis on its inalienable right to the civilian nuclear technology since the very beginning.
The United States, Russia, China, France and Britain plus Germany, in a statement after a meeting of senior diplomats in London late April, announced that they would ask European Union foreign policy chief Javier Solana to invite Tehran to the talks to find "a diplomatic solution to this critical issue".
"We strongly urge Iran to take advantage of this opportunity to engage seriously with all of us in a spirit of mutual respect," the six powers said in their statement.
As regards Iran's position on Iraq and Afghanistan, Najjar said, "The Islamic Republic of Iran has shown in practice that it wants to maintain stability in the region and as a powerful country it acts responsibly to maintain calm and peace in the region.
"Several rounds of Iran's constructive negotiations in Iraq and its efforts to strengthen the central government in Baghdad and help boost its power in maintaining stability in Iraq show the Islamic Republic of Iran's goodwill," he added.