A deal on Europe’s future, stitched together at last week’s bad-tempered summit, began to unravel yesterday after the intervention of the EU’s most unpredictable leader.

Jaroslaw Kaczynski, the Polish Prime Minister, who sent his brother Lech, the President, to the summit, stunned Brussels by declaring his determination to renegotiate the compromise. The twins spent much of last week’s detailed negotiations on the phone to each other and Lech had said that his brother was content with the package. But Jaroslaw, who demanded extra voting power for Poland, insisted yesterday that the deal had not taken full account of Poland’s demands.

Now he wants a permanent mechanism that allows a minority of dissenting states to be able to delay EU decisions for up to two years. His latest outburst has alarmed EU leaders, who were hoping for a trouble-free passage to a final text in October and a signing ceremony in December. An Inter-Governmental Conference will open on July 23, with representatives from all 27 EU nations to write the EU reform treaty, which critics say will be a thinly disguised version of the failed EU constitution.

With general agreement on the contents, all seemed to be going smoothly until Jaroslaw Kaczynski, referring to the deal to delay new voting weights for each country, said: “We have to finally resolve this issue at the Inter-Governmental Conference.” The European Commission responded furiously. “This was clearly settled at the European Council last week,” a spokesman said. “A mandate is a mandate and a deal is a deal. Now it is time for IGC to finish its job.”

A bluffer's guide to the EU treaty

Our correspondent hacks through the verbiage to explain what happened at the EU summit and what it means

• Patchwork deal proves Europe cannot heal its deepest wounds

BACKGROUND

• Unconstitutional

• Fresh start or revived constitution?

• Merkel’s dream; Britain’s nightmare

• Brown’s first test: how to avoid an EU constitution

• Europe divided over summit plans

Related Links

• Bleary-eyed Blair claims victory

• Poland ‘is ready to wreck everything if our voting demands are not met’

Portugal, which takes over the EU’s rotating presidency from Germany tomorrow, said: “There was a deal at the highest level and we hope that deal will be respected.” A German government spokesman added: “The outcome of the summit was unanimously backed and Poland agreed to it.”

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