§ Of the Rings of Power and the Third Age The Silmarillion

Thus Narsil came in due time to the hand of Valandil, Isildur's heir, in Imladris; but the blade was broken and its light was extinguished, and it was not forged anew. And Master Elrond foretold that this would not be done until the Ruling Ring should be found again and Sauron should return; but the hope of Elves and Men was that these things might never come to pass.