SEOUL, May 8 (Reuters) - North Korean leader Kim Jong Un said his country will not use nuclear weapons unless its sovereignty is infringed on by others with nuclear arms and it is willing to normalize ties with states that had been hostile towards it, state media reported on Sunday.

The North will faithfully fulfill its obligation for nuclear non-proliferation and strive for ending nuclear buildup in the world, Kim said in a report to a congress of its ruling party which opened on Friday, KCNA news agency said. (Reporting by Jack Kim; Editing by James Dalgleish)