Denis Staunton sums up the way the European Parliament will be affected by Nice.
The influence of the European Parliament has increased substantially and its approval is now required for most measures adopted by the EU. The parliament does not have the right to initiate legislation but it approves most Commission proposals in "co-decisions" with the Council of Ministers.
The Nice Treaty extends slightly the number of policy areas for which the parliament's approval is required.
It also gives the parliament a role in determining what action to take against member-states which breach the fundamental principles of the EU.
The treaty calls on the Council of Ministers and the parliament to draw up rules to govern the recognition and funding of pan-European political parties. Most national parties already belong to such groups but the treaty's critics fear that the new rules could discriminate against smaller parties and those opposed to European integration.
Nice raises the limit on seats in the European Parliament from 700 to 732 but in an enlarged EU, all member-states except Germany would have fewer seats in parliament than at present. Ireland's representation would fall from 15 to 12.