DUBLIN - Ireland's Supreme Court ruled on Friday that parliament cannot ratify the European Union's free trade deal with Canada unless legislation is changed, stating that the agreement is unconstitutional as Irish law now stands.

The Comprehensive Economic and Trade Agreement (CETA) sets out the removal of tariffs on 99% of all goods types traded between the EU and Canada, some over a period of up to seven years.

It has been provisionally in force since September 2017, and has so far been ratified by Canada and 16 of the 27 EU countries.

The Irish government had intended to ratify the agreement through a vote in parliament.

However a member of the ruling coalition challenged it in the courts, arguing that the deal should be put to a referendum because its ratification may impact on the ability to introduce regulation, particularly in relation to the environment.

(Reporting by Padraic Halpin)