The U.N. Security Council on Friday rejected a last-ditch effort to delay reimposing sanctions on Iran over its nuclear program, a decision that the country's president immediately called “unfair, unjust and illegal.

Tehran and Moscow have signed a $25bn deal to build four nuclear power reactors in southern Iran, according to Iranian state media. Friday’s announcement comes as the United Nations Security Council is expected to vote on a China- and Russia-backed resolution seeking delay,