Moody’s downgraded Greece’s bond ratings by a further three notches Monday and warned that it is almost inevitable the country will be considered to be in default following last week’s new bailout package.

The agency said the new EU package of measures implies “substantial’’ losses for private creditors. As a result, it cut its rating on Greece by three notches to Ca — one above what it considers a default rating. It also put eight Greek banks on review for a possible downgrade.