The Green Party must decide if it is to be a critical outsider on the European Union, or opt to drive change from within, one of the party's newly appointed senators, Deirdre de Búrca, has said.
"These are hard questions that will have to be considered by members when we gather over the next month or two to decide our position on the EU reform treaty," she told a conference of European green parties in Vienna on Saturday.
The Irish Greens had campaigned "against the ratification of successive EU treaties, back as far as the Single European Act", she said, and had adopted a policy of "critical engagement" with the EU.
The reform treaty, which will be put to a referendum in Ireland, next year, is "a complex document and contains both positive and negative elements", though she acknowledged that it would "certainly increase the efficiency of an enlarged union".
"The extension of QMV [qualified majority voting] to approximately 40 new areas, including energy policy and humanitarian aid policy, will ensure that political decision-making is more efficient.
"The simultaneous extension of the co-decision legislative procedure - giving the European Parliament a more equal say with the Council of Ministers in the general lawmaking process - is also welcome, as it strengthens the parliamentary dimension of the EU's democratic legitimacy," she declared.
The greater role for national parliaments and the inclusion of the Charter of Fundamental Rights and Freedoms in a protocol to the treaty was a significant move, she told the conference.
"For the first time ever, this treaty also sets out a mechanism for a member state to negotiate and conclude with other member states a withdrawal agreement from the union," she said.
Acknowledging most improvements in the environment in Ireland had come from EU action, she said the new treaty made welcome commitments to tackling climate change.
However, it also declares the EU "will", rather than "might" develop a common foreign and security policy, and will require states to "undertake to progressively improve their military capabilities" and to make "civilian and military capabilities available to the union for the implementation of the common security and defence policy".
