WASHINGTON (Reuters) - Quad countries -- an informal grouping of Australia, Japan, India and the United States -- on Friday condemned North Korea's "destabilising" ballistic missile launches and reaffirmed their commitment to the country's complete denuclearisation.

       In a statement, the four countries also said they reaffirmed their commitment to upholding and strengthening the "rules-based" multilateral trading system and to opposing "coercive economic policies" that run counter to this.

       (Reporting by Kirsty Needham and Humeyra Pamuk; editing by Philippa Fletcher)