Gaza's Hamas prime minister Ismail Haniya will not attend an upcoming Non-Aligned Movement summit in Tehran, Taher al-Nunu, a spokesman for the Hamas government, said on Sunday. "The prime minister received a generous invitation from the Iranian president to participate in the NAM summit," he wrote in a statement, adding that Haniya initially "said he might be going but he decided today to apologise." It was a swift U-turn for the Islamist movement which had on Saturday announced that Haniya would attend the summit following an "invitation from Iranian President Mahmoud Ahmadinejad." Iran's foreign ministry confirmed that Haniya had been invited to the gathering as a "special guest." But the announcement sparked a furious response from the rival Ramallah-based Palestinian Authority, with foreign minister Riyad al-Malki saying president Mahmud Abbas would boycott the summit if Haniya attended.