Kaczysnki said two days of negotiations at the EU conference in Brussels "have not achieved what we consider the absolute minimum" and he does not believe the situation will change. He said he believed the situation "would end up with a veto."
His twin brother, Polish President Lech Kaczynski, met with German Chancellor Angela Merkel three times today in Brussels but failed to find agreement.
The EU's rotating German presidency is the author of the proposed reform treaty, which is intended at making agreement among bloc nations easier to reach.
In the face of Poland’s continued opposition, Germany announced tonight that it is prepared to push ahead with negotiations. Merkel's spokesman, Ulrich Wilhelm, said Germany hoped to give Poland "an opportunity to join the consensus" later on.
There was no immediate reaction from the Poles to the German decision.
New Rules For Enlarged Bloc
Proponents argue that a new treaty to streamline EU institutions is necessary to allow the bloc to function effectively now that it has expanded to include 12 new members.
The proposed treaty would introduce a "double majority" voting system, requiring that decisions receive support from 55 percent of member states, representing at least 65 percent of the total EU population.
The new rules would increase Germany's influence and drastically reduce Poland’s.
In an interview, Kaczynski blamed Germany for population losses Poland incurred in World War II, saying it would have had 66 million people now instead of its current 38 million if not for the Nazis.
Poland went into the summit demanding greater voting power in EU majority votes in relation to Germany. Poland -- which has less than half the population of Germany -- currently has 27 votes compared to Germany’s 29.
At the close of the first day of talks, European Commission president Jose Manuel Barroso hinted that Poland's intransigence could taint all the new entrants.
"'We want the new member states not to give arguments for those who are against this great reunification of Europe," Barroso said. "So we are asking all the member states, but also the new member states, to show that those that pretend it was a mistake, the [EU] enlargement, they were wrong."
Poland's current leadership has a troubled relationship with Germany, which it accuses of pandering to Russia. Prime Minister Kaczynski also used a pre-summit radio interview to blame Germany for the population losses Poland incurred as a result of World War II, saying it would have had 66 million people now instead of its current 38 million had it not been for the Nazis.
Possible compromises aired so far include giving Poland extra powers to delay -- but not block -- EU legislation, or to delay the application of the new voting rules until 2014 or 2020. There has also been talk of raising the population threshold so that all new member states together could form a blocking minority.
Poland's attempts to guarantee a blocking minority for new member states are significant because EU development assistance to poorer member states would become subject to majority votes under the new "reform treaty." 2014 and 2020 are starting dates for the EU's next two seven-year budget cycles.
Without a veto, Poland appears to fear the rejection of its next budget requests -- and the funds in question are considerable. In the current 2007-2013 budget they amount to 36 per cent, or 308 billion euros, for all poor EU regions taken together. Poland is the largest single beneficiary.
These calculations also put in a clearer perspective Barroso's warning to the new member states.
Polish President Lech Kaczynski (left) with Angela Merkel on June 21 (epa)
Expanding majority decisions is a key part of the new treaty and is supported by an overwhelming majority of member states. A large majority of member states also believes there can be no further enlargement without institutional reforms, among them new voting rules.
This means the constitutional wrangle affects all of the western Balkan countries, as well as Turkey. By extension, the ambitions of European Neighborhood Policy countries to move closer to the EU would also suffer.
More Reforms Ahead
Other important reforms being discussed by EU leaders are creating the posts of EU president and foreign minister, enacting a new "charter of fundamental rights," curbing member state veto rights in justice and home affairs -- including immigration -- and extending existing social security provisions.
All of these moves are to a smaller or greater degree contested by Britain, the Netherlands and the Czech Republic, but diplomats say Germany believes these differences can be overcome and none of the countries would resort to a veto.
A deal at the ongoing summit would mean EU lawyers and diplomats would get a mandate to hammer out the finer points of the new treaty by the end of 2007. The treaty would then be ratified by all 27 member states and take effect in mid-2009, in time for the next European Parliament elections.
If there is no deal, the EU would find itself in a crisis in many ways far more serious than that which followed the rejection of the constitution by France and the Netherlands in 2005.
Not only would there be no treaty reform, but hopes for one would recede further. The internal discord that follows would put further enlargement on indefinite hold and significantly undermine the EU's ability to conduct an effective foreign policy.
To view RFE/RL's archive of coverage related to EU expansion, click here .