[JURIST] European Commission President Jose Manuel Barroso [official profile] urged EU member states to compromise to resolve key differences in negotiations over the proposed constitutional treaty [JURIST news archive] during a press conference [video excerpts; talking points, PDF] Tuesday, reiterating that the EU must continue to demonstrate pragmatism, flexibility, and unity to iron out its differences. He also asked state leaders to refrain from using the "outdated language of victory or defeat."

Barroso's comments follow strong statements from UK Prime Minister Tony Blair and Polish Prime Minister Jaroslaw Kaczynski [official profiles] setting rigid non-negotiable demands for their approval of the EU treaty. On Monday, Blair identified four non-negotiable issues [JURIST report] for the UK. Kaczynski said last week that Poland will not agree to any proposed treaty [JURIST report] unless negotiations on EU's voting system remained open to increase Poland's comparative voting power. On Friday, Kaczynski expressed optimism [JURIST report] following a meeting with French President Nicolas Sarkozy, but Polish officials saw little chance of a breakthrough with German Chancellor Angela Merkel, who remains doubtful [JURIST report] about what can actually be accomplished at the Brussels summit. Blair and Sarkozy have agreed that the controversial European constitution should be reconstituted into a "simplified treaty" [JURIST report] whose ratification would not require the support of the voters of the individual countries. In 2005, voters in France and the Netherlands [JURIST reports] rejected the original draft constitution in national referenda, effectively derailing the ratification process and throwing the constitution into legal limbo. BBC News has more.