A motion moved by Independent Alice Mary Higgins to stop Ireland signing up to a free trade agreement between the EU and Canada was passed by one vote in the Seanad.
It was opposed by Fine Gael, but supported by Sinn Féin, Labour and several Independents. Fianna Fáil, whose Senators spoke against the motion, abstained.
Ms Higgins claimed the pact, known as CETA, the comprehensive economic trade agreement, was part of a “new generation” of trade deals. She called on Ireland to oppose its “provisional application”.
They were radically different from previous trade agreements, notably in their introduction of special powers for corporations to sue governments and influence public regulation, she said.
“It is an absolute game-changer with the potential to affect our public services, environment and policy decisions in a way we have not seen before,” said Ms Higgins.
Fine Gael Senator Dr James Reilly said the deal would offer great opportunity to Irish producers, SMEs and create more Irish jobs.
“We are a small, open economy and we stand to gain an awful lot more from the access to a further large market like Canada through the EU,” he added.
Fianna Fáil Senator Gerry Horkan said the agreement was "ambitious and comprehensive" and would benefit Ireland in terms of increased jobs and business opportunities.
“The opportunities presented by this agreement will be especially relevant for SMEs, given that trade barriers tend to disproportionately burden smaller firms which have fewer resources to overcome larger firms,” he added.
CETA, he said, would remove over 99 per cent of tariffs between the two economies and create sizeable new market opportunities.